Block #316,654

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/17/2013, 5:07:29 AM · Difficulty 10.1392 · 6,489,406 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c4b9ac3f3b7b54ec4f74716dd3fa0aaf0ac582c38595f69dd760905d86d452f4

Height

#316,654

Difficulty

10.139150

Transactions

3

Size

1.73 KB

Version

2

Bits

0a239f58

Nonce

105,369

Timestamp

12/17/2013, 5:07:29 AM

Confirmations

6,489,406

Merkle Root

efde3b9ab91c4ae57486e55957b02ebac3d6d8f3d9e413204a8d42f0d3f21caa
Transactions (3)
1 in → 1 out9.7412 XPM110 B
2 in → 1 out35.0600 XPM339 B
8 in → 1 out2.7300 XPM1.20 KB
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.

3.740 × 10¹⁰⁵(106-digit number)
37407465478758977632…11807640889230633599
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
3.740 × 10¹⁰⁵(106-digit number)
37407465478758977632…11807640889230633599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.740 × 10¹⁰⁵(106-digit number)
37407465478758977632…11807640889230633601
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
7.481 × 10¹⁰⁵(106-digit number)
74814930957517955264…23615281778461267199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.481 × 10¹⁰⁵(106-digit number)
74814930957517955264…23615281778461267201
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
1.496 × 10¹⁰⁶(107-digit number)
14962986191503591052…47230563556922534399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.496 × 10¹⁰⁶(107-digit number)
14962986191503591052…47230563556922534401
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
2.992 × 10¹⁰⁶(107-digit number)
29925972383007182105…94461127113845068799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.992 × 10¹⁰⁶(107-digit number)
29925972383007182105…94461127113845068801
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
5.985 × 10¹⁰⁶(107-digit number)
59851944766014364211…88922254227690137599
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.985 × 10¹⁰⁶(107-digit number)
59851944766014364211…88922254227690137601
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:57,692,564 XPM·at block #6,806,059 · updates every 60s
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