Block #269,430

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/23/2013, 3:32:32 AM · Difficulty 9.9532 · 6,522,482 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
2e71925b07fec60ac83ef1925a031a64510729fc1fea250642bba0a4c8423eab

Height

#269,430

Difficulty

9.953177

Transactions

5

Size

1.91 KB

Version

2

Bits

09f40364

Nonce

392,122

Timestamp

11/23/2013, 3:32:32 AM

Confirmations

6,522,482

Merkle Root

001082955db7b0ba2344ea741c26575f8d3b201cc5270c5e7050996ea267e6ca
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.

3.427 × 10⁹²(93-digit number)
34272802933403857181…56014046378285792359
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
3.427 × 10⁹²(93-digit number)
34272802933403857181…56014046378285792359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.427 × 10⁹²(93-digit number)
34272802933403857181…56014046378285792361
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
6.854 × 10⁹²(93-digit number)
68545605866807714362…12028092756571584719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.854 × 10⁹²(93-digit number)
68545605866807714362…12028092756571584721
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
1.370 × 10⁹³(94-digit number)
13709121173361542872…24056185513143169439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.370 × 10⁹³(94-digit number)
13709121173361542872…24056185513143169441
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
2.741 × 10⁹³(94-digit number)
27418242346723085744…48112371026286338879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.741 × 10⁹³(94-digit number)
27418242346723085744…48112371026286338881
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
5.483 × 10⁹³(94-digit number)
54836484693446171489…96224742052572677759
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:57,579,248 XPM·at block #6,791,911 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.