Block #357,869

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/13/2014, 4:36:59 PM · Difficulty 10.3894 · 6,437,087 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
0c98b0fc033fd262bebeb00270c8c38f7260a0efa30e427b7e190fa3b02d1832

Height

#357,869

Difficulty

10.389387

Transactions

4

Size

3.05 KB

Version

2

Bits

0a63aed8

Nonce

5,934

Timestamp

1/13/2014, 4:36:59 PM

Confirmations

6,437,087

Merkle Root

94e6bae439da92adb8b8ecbfa86d3ccf618d4c5d5a82be14196aec15eaef5a4f
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.

9.427 × 10⁹³(94-digit number)
94275026478503395903…42737970264905131439
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
9.427 × 10⁹³(94-digit number)
94275026478503395903…42737970264905131439
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
9.427 × 10⁹³(94-digit number)
94275026478503395903…42737970264905131441
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
1.885 × 10⁹⁴(95-digit number)
18855005295700679180…85475940529810262879
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.885 × 10⁹⁴(95-digit number)
18855005295700679180…85475940529810262881
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
3.771 × 10⁹⁴(95-digit number)
37710010591401358361…70951881059620525759
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.771 × 10⁹⁴(95-digit number)
37710010591401358361…70951881059620525761
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
7.542 × 10⁹⁴(95-digit number)
75420021182802716722…41903762119241051519
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.542 × 10⁹⁴(95-digit number)
75420021182802716722…41903762119241051521
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
1.508 × 10⁹⁵(96-digit number)
15084004236560543344…83807524238482103039
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.508 × 10⁹⁵(96-digit number)
15084004236560543344…83807524238482103041
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:57,603,685 XPM·at block #6,794,955 · updates every 60s
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