Block #342,918

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/4/2014, 9:15:20 AM · Difficulty 10.1642 · 6,452,976 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
a7af48debf4c4895926672b5656aedda3650afa25e6cedaa46b1c1508eeffdd0

Height

#342,918

Difficulty

10.164189

Transactions

6

Size

1.51 KB

Version

2

Bits

0a2a0848

Nonce

11,745

Timestamp

1/4/2014, 9:15:20 AM

Confirmations

6,452,976

Merkle Root

457f117f1deab36d5c525a6c1ee3c0954a0bf4d97a1a1f11604ed01b05b2bc38
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.

8.945 × 10⁹⁶(97-digit number)
89459235655173690890…48093885970064853119
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
8.945 × 10⁹⁶(97-digit number)
89459235655173690890…48093885970064853119
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
8.945 × 10⁹⁶(97-digit number)
89459235655173690890…48093885970064853121
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
1.789 × 10⁹⁷(98-digit number)
17891847131034738178…96187771940129706239
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.789 × 10⁹⁷(98-digit number)
17891847131034738178…96187771940129706241
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
3.578 × 10⁹⁷(98-digit number)
35783694262069476356…92375543880259412479
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.578 × 10⁹⁷(98-digit number)
35783694262069476356…92375543880259412481
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
7.156 × 10⁹⁷(98-digit number)
71567388524138952712…84751087760518824959
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.156 × 10⁹⁷(98-digit number)
71567388524138952712…84751087760518824961
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
1.431 × 10⁹⁸(99-digit number)
14313477704827790542…69502175521037649919
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.431 × 10⁹⁸(99-digit number)
14313477704827790542…69502175521037649921
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:57,611,235 XPM·at block #6,795,893 · 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.