Block #654,728

TWNLength 11★★★☆☆

Bi-Twin Chain · Discovered 7/30/2014, 10:06:22 AM · Difficulty 10.9552 · 6,145,795 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
a5ea56ea5561114042dada78c8edc209a322bb857b2413fd637bd414495cb636

Height

#654,728

Difficulty

10.955241

Transactions

3

Size

693 B

Version

2

Bits

0af48aa9

Nonce

144,252,994

Timestamp

7/30/2014, 10:06:22 AM

Confirmations

6,145,795

Merkle Root

e9b333e5bee560212949223b2250d4749d2a8b4580196b8e927a7782624b80b9
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.

1.507 × 10⁹⁶(97-digit number)
15076300398242919353…93098815602696806399
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
1.507 × 10⁹⁶(97-digit number)
15076300398242919353…93098815602696806399
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.507 × 10⁹⁶(97-digit number)
15076300398242919353…93098815602696806401
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
3.015 × 10⁹⁶(97-digit number)
30152600796485838707…86197631205393612799
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.015 × 10⁹⁶(97-digit number)
30152600796485838707…86197631205393612801
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
6.030 × 10⁹⁶(97-digit number)
60305201592971677414…72395262410787225599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
6.030 × 10⁹⁶(97-digit number)
60305201592971677414…72395262410787225601
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
1.206 × 10⁹⁷(98-digit number)
12061040318594335482…44790524821574451199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.206 × 10⁹⁷(98-digit number)
12061040318594335482…44790524821574451201
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
2.412 × 10⁹⁷(98-digit number)
24122080637188670965…89581049643148902399
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.412 × 10⁹⁷(98-digit number)
24122080637188670965…89581049643148902401
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)
Level 5 — Twin Prime Pair (2^5 × origin ± 1)
2^5 × origin − 1
4.824 × 10⁹⁷(98-digit number)
48244161274377341931…79162099286297804799
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,648,251 XPM·at block #6,800,522 · updates every 60s
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