Block #726,335

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 9/17/2014, 8:41:32 PM · Difficulty 10.9610 · 6,068,248 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
b99a05aad6f869594406397e58ac86c199eba31e358cd92262c76e23c6e8f2c3

Height

#726,335

Difficulty

10.960955

Transactions

5

Size

2.21 KB

Version

2

Bits

0af6011f

Nonce

656,573,055

Timestamp

9/17/2014, 8:41:32 PM

Confirmations

6,068,248

Merkle Root

6429e70a0ad7d8d8e36ddd95dce634a01df5b1dcbd063b092eb3d990fa295b6f
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.

1.006 × 10⁹⁹(100-digit number)
10062965603527651160…37078112177252362239
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
1.006 × 10⁹⁹(100-digit number)
10062965603527651160…37078112177252362239
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.006 × 10⁹⁹(100-digit number)
10062965603527651160…37078112177252362241
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
2.012 × 10⁹⁹(100-digit number)
20125931207055302321…74156224354504724479
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.012 × 10⁹⁹(100-digit number)
20125931207055302321…74156224354504724481
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
4.025 × 10⁹⁹(100-digit number)
40251862414110604643…48312448709009448959
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.025 × 10⁹⁹(100-digit number)
40251862414110604643…48312448709009448961
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
8.050 × 10⁹⁹(100-digit number)
80503724828221209286…96624897418018897919
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.050 × 10⁹⁹(100-digit number)
80503724828221209286…96624897418018897921
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
1.610 × 10¹⁰⁰(101-digit number)
16100744965644241857…93249794836037795839
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.610 × 10¹⁰⁰(101-digit number)
16100744965644241857…93249794836037795841
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:57,600,711 XPM·at block #6,794,582 · updates every 60s
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