Block #312,210

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/14/2013, 10:10:09 PM · Difficulty 9.9957 · 6,490,282 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
a3461c2d131d1d8f04204ff7418bd6acd07c82a19c079c02a0369051e0cf2891

Height

#312,210

Difficulty

9.995739

Transactions

8

Size

2.68 KB

Version

2

Bits

09fee8c2

Nonce

63,662

Timestamp

12/14/2013, 10:10:09 PM

Confirmations

6,490,282

Merkle Root

b2100ced83d7d73b687faf4218e818cc6078ab37787eac32c64fa8b495e499cd
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.

2.941 × 10⁹³(94-digit number)
29419005294771833190…90920661088337907199
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
2.941 × 10⁹³(94-digit number)
29419005294771833190…90920661088337907199
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.941 × 10⁹³(94-digit number)
29419005294771833190…90920661088337907201
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
5.883 × 10⁹³(94-digit number)
58838010589543666380…81841322176675814399
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.883 × 10⁹³(94-digit number)
58838010589543666380…81841322176675814401
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
1.176 × 10⁹⁴(95-digit number)
11767602117908733276…63682644353351628799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.176 × 10⁹⁴(95-digit number)
11767602117908733276…63682644353351628801
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
2.353 × 10⁹⁴(95-digit number)
23535204235817466552…27365288706703257599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.353 × 10⁹⁴(95-digit number)
23535204235817466552…27365288706703257601
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
4.707 × 10⁹⁴(95-digit number)
47070408471634933104…54730577413406515199
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.707 × 10⁹⁴(95-digit number)
47070408471634933104…54730577413406515201
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:57,663,950 XPM·at block #6,802,491 · updates every 60s
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