Home/Chain Registry/Block #201,497

Block #201,497

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 10/9/2013, 4:31:32 PM · Difficulty 9.8917 · 6,601,707 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
134423cce20b7c071d238cbbe24a5b79fb30393b8ee81d489dcb816b144a32ec

Height

#201,497

Difficulty

9.891739

Transactions

8

Size

2.96 KB

Version

2

Bits

09e448fb

Nonce

34,776

Timestamp

10/9/2013, 4:31:32 PM

Confirmations

6,601,707

Merkle Root

c63a094b9d644ab0a0f91e6e8ab52332ccfa6b9633084838adf4c07ff381da38
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.

1.169 × 10⁹⁴(95-digit number)
11698314726508260889…14484558890708565640
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
1.169 × 10⁹⁴(95-digit number)
11698314726508260889…14484558890708565639
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.169 × 10⁹⁴(95-digit number)
11698314726508260889…14484558890708565641
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
2.339 × 10⁹⁴(95-digit number)
23396629453016521778…28969117781417131279
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.339 × 10⁹⁴(95-digit number)
23396629453016521778…28969117781417131281
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
4.679 × 10⁹⁴(95-digit number)
46793258906033043557…57938235562834262559
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.679 × 10⁹⁴(95-digit number)
46793258906033043557…57938235562834262561
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
9.358 × 10⁹⁴(95-digit number)
93586517812066087115…15876471125668525119
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
9.358 × 10⁹⁴(95-digit number)
93586517812066087115…15876471125668525121
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
1.871 × 10⁹⁵(96-digit number)
18717303562413217423…31752942251337050239
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.871 × 10⁹⁵(96-digit number)
18717303562413217423…31752942251337050241
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)

What this block proved

The miner who found this block proved the existence of 10 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
UncommonChain length 10
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 201497

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 134423cce20b7c071d238cbbe24a5b79fb30393b8ee81d489dcb816b144a32ec

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 #201,497 on Chainz ↗
Circulating Supply:57,669,654 XPM·at block #6,803,203 · updates every 60s
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