Block #418,850

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/25/2014, 5:03:09 AM · Difficulty 10.3830 · 6,376,393 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
076367af4beaf344b496389fab4b9fcd18a29d33d250f8138c77a059b162f012

Height

#418,850

Difficulty

10.383007

Transactions

4

Size

1.58 KB

Version

2

Bits

0a620cc5

Nonce

195,722

Timestamp

2/25/2014, 5:03:09 AM

Confirmations

6,376,393

Merkle Root

946af7f6ee28657628bbc7078038e77edd331f403871a1aa20536633d3473126
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.

9.812 × 10⁹⁵(96-digit number)
98126907796847439372…42422004137499948479
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
9.812 × 10⁹⁵(96-digit number)
98126907796847439372…42422004137499948479
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
9.812 × 10⁹⁵(96-digit number)
98126907796847439372…42422004137499948481
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
1.962 × 10⁹⁶(97-digit number)
19625381559369487874…84844008274999896959
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.962 × 10⁹⁶(97-digit number)
19625381559369487874…84844008274999896961
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
3.925 × 10⁹⁶(97-digit number)
39250763118738975748…69688016549999793919
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.925 × 10⁹⁶(97-digit number)
39250763118738975748…69688016549999793921
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
7.850 × 10⁹⁶(97-digit number)
78501526237477951497…39376033099999587839
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.850 × 10⁹⁶(97-digit number)
78501526237477951497…39376033099999587841
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
1.570 × 10⁹⁷(98-digit number)
15700305247495590299…78752066199999175679
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.570 × 10⁹⁷(98-digit number)
15700305247495590299…78752066199999175681
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:57,605,999 XPM·at block #6,795,242 · updates every 60s
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