Block #337,138

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/31/2013, 11:04:48 AM · Difficulty 10.1406 · 6,458,550 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
2e0348f50cdd0d07c84451c36e5aa2c73ec7451374f7e9f9bb4d71796d108135

Height

#337,138

Difficulty

10.140648

Transactions

2

Size

427 B

Version

2

Bits

0a240189

Nonce

377,534

Timestamp

12/31/2013, 11:04:48 AM

Confirmations

6,458,550

Merkle Root

7e57fb1607b5fa02e61bb7c279ea70a280d05881bc3c8467d56acb208f20a225
Transactions (2)
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.

3.394 × 10⁹⁶(97-digit number)
33940170356073015455…59699033278399286399
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
3.394 × 10⁹⁶(97-digit number)
33940170356073015455…59699033278399286399
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.394 × 10⁹⁶(97-digit number)
33940170356073015455…59699033278399286401
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
6.788 × 10⁹⁶(97-digit number)
67880340712146030911…19398066556798572799
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.788 × 10⁹⁶(97-digit number)
67880340712146030911…19398066556798572801
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
1.357 × 10⁹⁷(98-digit number)
13576068142429206182…38796133113597145599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.357 × 10⁹⁷(98-digit number)
13576068142429206182…38796133113597145601
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
2.715 × 10⁹⁷(98-digit number)
27152136284858412364…77592266227194291199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.715 × 10⁹⁷(98-digit number)
27152136284858412364…77592266227194291201
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
5.430 × 10⁹⁷(98-digit number)
54304272569716824729…55184532454388582399
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.430 × 10⁹⁷(98-digit number)
54304272569716824729…55184532454388582401
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.

★★☆☆☆
Rarity
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

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
Circulating Supply:57,609,573 XPM·at block #6,795,687 · updates every 60s
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