Block #472,617

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/3/2014, 9:45:13 AM · Difficulty 10.4368 · 6,320,381 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
3bd5f6d909f3a0ce78a096c7c732044a21a9dc80d773dcbc2e63be695e0bb454

Height

#472,617

Difficulty

10.436849

Transactions

8

Size

3.08 KB

Version

2

Bits

0a6fd555

Nonce

2,877

Timestamp

4/3/2014, 9:45:13 AM

Confirmations

6,320,381

Merkle Root

f7856802130b403e72664eb85e27e6615763ae0d18b83a1cebd7afef75628b85
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.

1.131 × 10⁹⁸(99-digit number)
11316053924283435760…71054968203190954639
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
1.131 × 10⁹⁸(99-digit number)
11316053924283435760…71054968203190954639
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.131 × 10⁹⁸(99-digit number)
11316053924283435760…71054968203190954641
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
2.263 × 10⁹⁸(99-digit number)
22632107848566871521…42109936406381909279
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.263 × 10⁹⁸(99-digit number)
22632107848566871521…42109936406381909281
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
4.526 × 10⁹⁸(99-digit number)
45264215697133743042…84219872812763818559
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.526 × 10⁹⁸(99-digit number)
45264215697133743042…84219872812763818561
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
9.052 × 10⁹⁸(99-digit number)
90528431394267486085…68439745625527637119
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
9.052 × 10⁹⁸(99-digit number)
90528431394267486085…68439745625527637121
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
1.810 × 10⁹⁹(100-digit number)
18105686278853497217…36879491251055274239
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.810 × 10⁹⁹(100-digit number)
18105686278853497217…36879491251055274241
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:57,587,968 XPM·at block #6,792,997 · updates every 60s
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