Block #126,589

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 8/20/2013, 11:48:01 PM · Difficulty 9.7810 · 6,663,244 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
5927f161bd55dc75482bb6748784453917c48966f13788af8a0cada6fa3474b4

Height

#126,589

Difficulty

9.781009

Transactions

5

Size

2.66 KB

Version

2

Bits

09c7f039

Nonce

29,371

Timestamp

8/20/2013, 11:48:01 PM

Confirmations

6,663,244

Merkle Root

38e51a36d23eb5448bd851d4a08050ac46ea68e0206abbc89524320874fa9b81
Transactions (5)
1 in → 1 out10.4900 XPM109 B
1 in → 1 out199.9900 XPM193 B
4 in → 1 out42.0000 XPM499 B
1 in → 1 out10.4800 XPM158 B
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.

4.447 × 10¹⁰⁵(106-digit number)
44479981619273198725…32856389193342797359
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
4.447 × 10¹⁰⁵(106-digit number)
44479981619273198725…32856389193342797359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.447 × 10¹⁰⁵(106-digit number)
44479981619273198725…32856389193342797361
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
8.895 × 10¹⁰⁵(106-digit number)
88959963238546397450…65712778386685594719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
8.895 × 10¹⁰⁵(106-digit number)
88959963238546397450…65712778386685594721
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
1.779 × 10¹⁰⁶(107-digit number)
17791992647709279490…31425556773371189439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.779 × 10¹⁰⁶(107-digit number)
17791992647709279490…31425556773371189441
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
3.558 × 10¹⁰⁶(107-digit number)
35583985295418558980…62851113546742378879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.558 × 10¹⁰⁶(107-digit number)
35583985295418558980…62851113546742378881
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
7.116 × 10¹⁰⁶(107-digit number)
71167970590837117960…25702227093484757759
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,562,635 XPM·at block #6,789,832 · updates every 60s