Block #330,905

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/27/2013, 12:08:56 AM · Difficulty 10.1684 · 6,474,279 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c6c68851aa6553eb4da135462cc9889745eae3195173332b55833372536c3221

Height

#330,905

Difficulty

10.168382

Transactions

3

Size

653 B

Version

2

Bits

0a2b1b1b

Nonce

28,887

Timestamp

12/27/2013, 12:08:56 AM

Confirmations

6,474,279

Merkle Root

be431e148cb68593b3358d4c2e7ff18b004dbf8682d297870903a1c7f6020dd9
Transactions (3)
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.

1.914 × 10⁹⁶(97-digit number)
19147399684300931705…27634114701945034719
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
1.914 × 10⁹⁶(97-digit number)
19147399684300931705…27634114701945034719
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.914 × 10⁹⁶(97-digit number)
19147399684300931705…27634114701945034721
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
3.829 × 10⁹⁶(97-digit number)
38294799368601863411…55268229403890069439
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.829 × 10⁹⁶(97-digit number)
38294799368601863411…55268229403890069441
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
7.658 × 10⁹⁶(97-digit number)
76589598737203726823…10536458807780138879
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
7.658 × 10⁹⁶(97-digit number)
76589598737203726823…10536458807780138881
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
1.531 × 10⁹⁷(98-digit number)
15317919747440745364…21072917615560277759
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.531 × 10⁹⁷(98-digit number)
15317919747440745364…21072917615560277761
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
3.063 × 10⁹⁷(98-digit number)
30635839494881490729…42145835231120555519
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.063 × 10⁹⁷(98-digit number)
30635839494881490729…42145835231120555521
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:57,685,542 XPM·at block #6,805,183 · updates every 60s
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