Block #1,177,266

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 7/30/2015, 5:08:59 PM · Difficulty 10.9362 · 5,627,866 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
9b2780d927cab1fb92393b5aaba95b26fe901e87218354f1b083e4f6558a2f4b

Height

#1,177,266

Difficulty

10.936234

Transactions

3

Size

3.43 KB

Version

2

Bits

0aefad09

Nonce

1,471,708,946

Timestamp

7/30/2015, 5:08:59 PM

Confirmations

5,627,866

Merkle Root

b1bcbfc5c5f2a6eb7e3626d689ad13a04c9d549097cdc1f050cfe743a477111a
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.

1.034 × 10⁹⁵(96-digit number)
10340593603722069224…64851212043192185599
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
1.034 × 10⁹⁵(96-digit number)
10340593603722069224…64851212043192185599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.034 × 10⁹⁵(96-digit number)
10340593603722069224…64851212043192185601
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
2.068 × 10⁹⁵(96-digit number)
20681187207444138448…29702424086384371199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.068 × 10⁹⁵(96-digit number)
20681187207444138448…29702424086384371201
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
4.136 × 10⁹⁵(96-digit number)
41362374414888276896…59404848172768742399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.136 × 10⁹⁵(96-digit number)
41362374414888276896…59404848172768742401
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
8.272 × 10⁹⁵(96-digit number)
82724748829776553792…18809696345537484799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.272 × 10⁹⁵(96-digit number)
82724748829776553792…18809696345537484801
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
1.654 × 10⁹⁶(97-digit number)
16544949765955310758…37619392691074969599
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.654 × 10⁹⁶(97-digit number)
16544949765955310758…37619392691074969601
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:57,685,120 XPM·at block #6,805,131 · updates every 60s
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