Block #316,035

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/16/2013, 8:22:20 PM · Difficulty 10.1230 · 6,489,142 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
eb4c879c13786429852af171210e0aa61cdd2c9c1798a0bf17394d97200e3491

Height

#316,035

Difficulty

10.123029

Transactions

10

Size

2.33 KB

Version

2

Bits

0a1f7ecf

Nonce

320,137

Timestamp

12/16/2013, 8:22:20 PM

Confirmations

6,489,142

Merkle Root

5cddf7d8f7d9e174f62b0492eeea3fb8a8ea18155e8efe661c93bec7751a9f14
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.

1.234 × 10¹⁰⁴(105-digit number)
12347052748331354105…49999855892553495039
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
1.234 × 10¹⁰⁴(105-digit number)
12347052748331354105…49999855892553495039
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.234 × 10¹⁰⁴(105-digit number)
12347052748331354105…49999855892553495041
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
2.469 × 10¹⁰⁴(105-digit number)
24694105496662708211…99999711785106990079
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.469 × 10¹⁰⁴(105-digit number)
24694105496662708211…99999711785106990081
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
4.938 × 10¹⁰⁴(105-digit number)
49388210993325416422…99999423570213980159
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.938 × 10¹⁰⁴(105-digit number)
49388210993325416422…99999423570213980161
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
9.877 × 10¹⁰⁴(105-digit number)
98776421986650832844…99998847140427960319
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
9.877 × 10¹⁰⁴(105-digit number)
98776421986650832844…99998847140427960321
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
1.975 × 10¹⁰⁵(106-digit number)
19755284397330166568…99997694280855920639
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.975 × 10¹⁰⁵(106-digit number)
19755284397330166568…99997694280855920641
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:57,685,485 XPM·at block #6,805,176 · 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.