Block #343,549

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/4/2014, 6:17:31 PM · Difficulty 10.1786 · 6,452,225 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
cd0d014981e552223af6b0daaf103efa1b60b4c098cfaec55e11b7b14d321e44

Height

#343,549

Difficulty

10.178600

Transactions

3

Size

651 B

Version

2

Bits

0a2db8b6

Nonce

14,891

Timestamp

1/4/2014, 6:17:31 PM

Confirmations

6,452,225

Merkle Root

a2a45b19346bd0554773f21eecb8c54a19c48cf5fc67d860cd9924dde8758d57
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.

3.167 × 10⁹⁰(91-digit number)
31677376837298771579…83236907587407027789
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
3.167 × 10⁹⁰(91-digit number)
31677376837298771579…83236907587407027789
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.167 × 10⁹⁰(91-digit number)
31677376837298771579…83236907587407027791
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
6.335 × 10⁹⁰(91-digit number)
63354753674597543158…66473815174814055579
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.335 × 10⁹⁰(91-digit number)
63354753674597543158…66473815174814055581
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
1.267 × 10⁹¹(92-digit number)
12670950734919508631…32947630349628111159
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.267 × 10⁹¹(92-digit number)
12670950734919508631…32947630349628111161
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
2.534 × 10⁹¹(92-digit number)
25341901469839017263…65895260699256222319
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.534 × 10⁹¹(92-digit number)
25341901469839017263…65895260699256222321
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
5.068 × 10⁹¹(92-digit number)
50683802939678034526…31790521398512444639
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.068 × 10⁹¹(92-digit number)
50683802939678034526…31790521398512444641
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:57,610,275 XPM·at block #6,795,773 · updates every 60s
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