Block #269,091

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/22/2013, 6:07:38 PM · Difficulty 9.9552 · 6,521,908 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
fa1d317ed5058ef3071bd38129011619282b963ae6e2e6682fad64fdd37ff935

Height

#269,091

Difficulty

9.955187

Transactions

6

Size

39.20 KB

Version

2

Bits

09f48729

Nonce

35,032

Timestamp

11/22/2013, 6:07:38 PM

Confirmations

6,521,908

Merkle Root

b55a2183069367101b75976ed0e3bae9854f70f4a8f802d7e84f227b28aa11ac
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.

1.411 × 10⁹²(93-digit number)
14116530486985002399…05007308932054179279
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
1.411 × 10⁹²(93-digit number)
14116530486985002399…05007308932054179279
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.411 × 10⁹²(93-digit number)
14116530486985002399…05007308932054179281
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
2.823 × 10⁹²(93-digit number)
28233060973970004799…10014617864108358559
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.823 × 10⁹²(93-digit number)
28233060973970004799…10014617864108358561
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
5.646 × 10⁹²(93-digit number)
56466121947940009599…20029235728216717119
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.646 × 10⁹²(93-digit number)
56466121947940009599…20029235728216717121
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
1.129 × 10⁹³(94-digit number)
11293224389588001919…40058471456433434239
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.129 × 10⁹³(94-digit number)
11293224389588001919…40058471456433434241
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
2.258 × 10⁹³(94-digit number)
22586448779176003839…80116942912866868479
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:57,572,007 XPM·at block #6,790,998 · updates every 60s