Block #1,324,940

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/13/2015, 6:58:38 AM · Difficulty 10.8530 · 5,480,237 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
367d2b04c83b3f78a654943c870f88eb4a2dc1edd432a0745394d8cf30bd6eeb

Height

#1,324,940

Difficulty

10.853007

Transactions

2

Size

16.33 KB

Version

2

Bits

0ada5eae

Nonce

1,013,610,220

Timestamp

11/13/2015, 6:58:38 AM

Confirmations

5,480,237

Merkle Root

97e4c28811592c9029f23b62a74b63111e3fd07840ef298a325282437ce94e39
Transactions (2)
1 in → 1 out8.6500 XPM110 B
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.

2.986 × 10⁹⁵(96-digit number)
29864045149983847922…22473749646425291599
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
2.986 × 10⁹⁵(96-digit number)
29864045149983847922…22473749646425291599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.986 × 10⁹⁵(96-digit number)
29864045149983847922…22473749646425291601
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
5.972 × 10⁹⁵(96-digit number)
59728090299967695844…44947499292850583199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.972 × 10⁹⁵(96-digit number)
59728090299967695844…44947499292850583201
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
1.194 × 10⁹⁶(97-digit number)
11945618059993539168…89894998585701166399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.194 × 10⁹⁶(97-digit number)
11945618059993539168…89894998585701166401
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
2.389 × 10⁹⁶(97-digit number)
23891236119987078337…79789997171402332799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.389 × 10⁹⁶(97-digit number)
23891236119987078337…79789997171402332801
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
4.778 × 10⁹⁶(97-digit number)
47782472239974156675…59579994342804665599
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.778 × 10⁹⁶(97-digit number)
47782472239974156675…59579994342804665601
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:57,685,485 XPM·at block #6,805,176 · updates every 60s
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