Block #431,031

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/5/2014, 9:52:05 PM · Difficulty 10.3455 · 6,360,968 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
69d961f83d8f0653954d0d5a8c3928df22b6197ace0c43866cef00ff4c56408f

Height

#431,031

Difficulty

10.345473

Transactions

7

Size

1.49 KB

Version

2

Bits

0a5870e8

Nonce

538,396

Timestamp

3/5/2014, 9:52:05 PM

Confirmations

6,360,968

Merkle Root

3e2785f9114f97e629f7dfb1d4f2120c55d506839bbaab82a94b06f29bc474c0
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.

4.631 × 10⁹⁷(98-digit number)
46311170374619430575…59467330839175065599
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
4.631 × 10⁹⁷(98-digit number)
46311170374619430575…59467330839175065599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.631 × 10⁹⁷(98-digit number)
46311170374619430575…59467330839175065601
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
9.262 × 10⁹⁷(98-digit number)
92622340749238861151…18934661678350131199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
9.262 × 10⁹⁷(98-digit number)
92622340749238861151…18934661678350131201
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
1.852 × 10⁹⁸(99-digit number)
18524468149847772230…37869323356700262399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.852 × 10⁹⁸(99-digit number)
18524468149847772230…37869323356700262401
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
3.704 × 10⁹⁸(99-digit number)
37048936299695544460…75738646713400524799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.704 × 10⁹⁸(99-digit number)
37048936299695544460…75738646713400524801
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
7.409 × 10⁹⁸(99-digit number)
74097872599391088920…51477293426801049599
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
7.409 × 10⁹⁸(99-digit number)
74097872599391088920…51477293426801049601
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:57,579,948 XPM·at block #6,791,998 · updates every 60s
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