Home/Chain Registry/Block #275,072

Block #275,072

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/26/2013, 1:27:36 PM · Difficulty 9.9596 · 6,517,937 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
b77630ac1009a0ff0e6887a295305e416a5ebd7ff54c64c2ce2f7b3e69ba641e

Height

#275,072

Difficulty

9.959611

Transactions

5

Size

3.75 KB

Version

2

Bits

09f5a911

Nonce

39,125

Timestamp

11/26/2013, 1:27:36 PM

Confirmations

6,517,937

Merkle Root

f92a4b3a57ddd2753928ac63095a95aeb4c9e6d4cc0fd4b67d91f59fc129174e
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.

8.611 × 10⁹¹(92-digit number)
86112582411254458665…99261177390804839040
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
8.611 × 10⁹¹(92-digit number)
86112582411254458665…99261177390804839039
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
8.611 × 10⁹¹(92-digit number)
86112582411254458665…99261177390804839041
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
1.722 × 10⁹²(93-digit number)
17222516482250891733…98522354781609678079
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.722 × 10⁹²(93-digit number)
17222516482250891733…98522354781609678081
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
3.444 × 10⁹²(93-digit number)
34445032964501783466…97044709563219356159
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.444 × 10⁹²(93-digit number)
34445032964501783466…97044709563219356161
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
6.889 × 10⁹²(93-digit number)
68890065929003566932…94089419126438712319
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
6.889 × 10⁹²(93-digit number)
68890065929003566932…94089419126438712321
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
1.377 × 10⁹³(94-digit number)
13778013185800713386…88178838252877424639
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9
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 275072

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 b77630ac1009a0ff0e6887a295305e416a5ebd7ff54c64c2ce2f7b3e69ba641e

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 #275,072 on Chainz ↗
Circulating Supply:57,588,056 XPM·at block #6,793,008 · updates every 60s
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