Block #1,043,671

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 5/3/2015, 10:46:19 PM · Difficulty 10.7220 · 5,748,147 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
64e94a5e1e6c263a6252f9c4c3e2cf5fb35c1711ad7f4b8faaaf847e5862baf0

Height

#1,043,671

Difficulty

10.722049

Transactions

2

Size

571 B

Version

2

Bits

0ab8d834

Nonce

1,111,130,620

Timestamp

5/3/2015, 10:46:19 PM

Confirmations

5,748,147

Merkle Root

3eb3b8b971732a16259fd5a04f6d87229fbae7dfff35e62f9a8737144f99a6b8
Transactions (2)
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.

7.808 × 10⁹¹(92-digit number)
78082187777072129579…99658787129313387479
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
7.808 × 10⁹¹(92-digit number)
78082187777072129579…99658787129313387479
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
7.808 × 10⁹¹(92-digit number)
78082187777072129579…99658787129313387481
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
1.561 × 10⁹²(93-digit number)
15616437555414425915…99317574258626774959
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.561 × 10⁹²(93-digit number)
15616437555414425915…99317574258626774961
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
3.123 × 10⁹²(93-digit number)
31232875110828851831…98635148517253549919
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.123 × 10⁹²(93-digit number)
31232875110828851831…98635148517253549921
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
6.246 × 10⁹²(93-digit number)
62465750221657703663…97270297034507099839
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
6.246 × 10⁹²(93-digit number)
62465750221657703663…97270297034507099841
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
1.249 × 10⁹³(94-digit number)
12493150044331540732…94540594069014199679
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.249 × 10⁹³(94-digit number)
12493150044331540732…94540594069014199681
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:57,578,491 XPM·at block #6,791,817 · updates every 60s
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