Block #1,266,110

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 10/4/2015, 2:26:06 AM · Difficulty 10.8200 · 5,530,338 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
1f1413f6828f6cb371ec77936797681a7df684910cf3a1e6cfdce909622aeeb5

Height

#1,266,110

Difficulty

10.819987

Transactions

6

Size

2.03 KB

Version

2

Bits

0ad1eaac

Nonce

125,373,054

Timestamp

10/4/2015, 2:26:06 AM

Confirmations

5,530,338

Merkle Root

ac45c7dbe87b7fb17cf1f6d0674fb58fbbb690e92d7ef2dd598b867a1a1cb940
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.

2.303 × 10⁹⁶(97-digit number)
23037636705232530309…31387795391777551439
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
2.303 × 10⁹⁶(97-digit number)
23037636705232530309…31387795391777551439
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.303 × 10⁹⁶(97-digit number)
23037636705232530309…31387795391777551441
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
4.607 × 10⁹⁶(97-digit number)
46075273410465060618…62775590783555102879
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.607 × 10⁹⁶(97-digit number)
46075273410465060618…62775590783555102881
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
9.215 × 10⁹⁶(97-digit number)
92150546820930121237…25551181567110205759
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
9.215 × 10⁹⁶(97-digit number)
92150546820930121237…25551181567110205761
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
1.843 × 10⁹⁷(98-digit number)
18430109364186024247…51102363134220411519
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.843 × 10⁹⁷(98-digit number)
18430109364186024247…51102363134220411521
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
3.686 × 10⁹⁷(98-digit number)
36860218728372048494…02204726268440823039
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.686 × 10⁹⁷(98-digit number)
36860218728372048494…02204726268440823041
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:57,615,578 XPM·at block #6,796,447 · updates every 60s
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