Home/Chain Registry/Block #497,181

Block #497,181

TWNLength 11★★★☆☆

Bi-Twin Chain · Discovered 4/17/2014, 11:25:40 AM · Difficulty 10.7640 · 6,308,579 confirmations

TWN
Bi-Twin Chain

Interleaved pairs of primes that differ by 2, forming twin prime pairs at each level.

Block Header
Block Hash
cf55bdbb3ffdd0c823e9b863602c2c37a1ca012d83abbb690dcbfc57dfb8c1df

Height

#497,181

Difficulty

10.763986

Transactions

7

Size

2.39 KB

Version

2

Bits

0ac3949a

Nonce

34,101

Timestamp

4/17/2014, 11:25:40 AM

Confirmations

6,308,579

Merkle Root

0291375df05b6861f49942d5f1a07a39d68fea632ac19cff8cd9ac5de09b1094
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

3.252 × 10⁹⁴(95-digit number)
32522680537850538471…97017409146046728000
Discovered Prime Numbers
Lower: 2^k × origin − 1 | Upper: 2^k × origin + 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

Level 0 — Twin Prime Pair (origin ± 1)
origin − 1
3.252 × 10⁹⁴(95-digit number)
32522680537850538471…97017409146046727999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.252 × 10⁹⁴(95-digit number)
32522680537850538471…97017409146046728001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: origin + 1 − origin − 1 = 2 (twin primes ✓)
Level 1 — Twin Prime Pair (2^1 × origin ± 1)
2^1 × origin − 1
6.504 × 10⁹⁴(95-digit number)
65045361075701076943…94034818292093455999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.504 × 10⁹⁴(95-digit number)
65045361075701076943…94034818292093456001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^1 × origin + 1 − 2^1 × origin − 1 = 2 (twin primes ✓)
Level 2 — Twin Prime Pair (2^2 × origin ± 1)
2^2 × origin − 1
1.300 × 10⁹⁵(96-digit number)
13009072215140215388…88069636584186911999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.300 × 10⁹⁵(96-digit number)
13009072215140215388…88069636584186912001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^2 × origin + 1 − 2^2 × origin − 1 = 2 (twin primes ✓)
Level 3 — Twin Prime Pair (2^3 × origin ± 1)
2^3 × origin − 1
2.601 × 10⁹⁵(96-digit number)
26018144430280430777…76139273168373823999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.601 × 10⁹⁵(96-digit number)
26018144430280430777…76139273168373824001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^3 × origin + 1 − 2^3 × origin − 1 = 2 (twin primes ✓)
Level 4 — Twin Prime Pair (2^4 × origin ± 1)
2^4 × origin − 1
5.203 × 10⁹⁵(96-digit number)
52036288860560861555…52278546336747647999
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.203 × 10⁹⁵(96-digit number)
52036288860560861555…52278546336747648001
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)
Level 5 — Twin Prime Pair (2^5 × origin ± 1)
2^5 × origin − 1
1.040 × 10⁹⁶(97-digit number)
10407257772112172311…04557092673495295999
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 consecutive prime numbers forming a Bi-Twin Chain. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

View full Prime Chain Discovery page →
★★★☆☆
Rarity
RareChain length 11
How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)
Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the TWN formula:

TWN: twin pairs (p, p+2) where p = origin/primorial − 1 and p+2 = origin/primorial + 1
Verify on a Primecoin Node

Anyone running a Primecoin node can independently verify this block using the following RPC commands. Run these from the primecoin-cli command line or via the debug console in the Primecoin wallet.

1. Get block hash by height
getblockhash 497181

Returns the block hash for a given block height. Use this to confirm the hash shown above matches the chain.

2. Get full block data
getblock cf55bdbb3ffdd0c823e9b863602c2c37a1ca012d83abbb690dcbfc57dfb8c1df

Returns the full block header including difficulty, prime chain origin, prime chain type, transaction IDs, and all other fields shown on this page.

How to run these commands: To verify this data independently, open a terminal on your own Primecoin node and run primecoin-cli <command>. Alternatively, open the Primecoin-Qt wallet, go to Help → Debug Window → Console, and type the command directly. The node must be fully synced to this block height for the commands to return results.

Cross-reference on Chainz Explorer

Chainz is an independent Primecoin block explorer. Compare this block's data to verify accuracy.

View Block #497,181 on Chainz ↗
Circulating Supply:57,690,163 XPM·at block #6,805,759 · updates every 60s
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