Block #299,040

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 12/7/2013, 5:22:41 PM · Difficulty 9.9920 · 6,499,873 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
b02377be4091cdd48557cc9cdf7057646fda8808677d4fe5d519cc8566ccb6c4

Height

#299,040

Difficulty

9.992037

Transactions

13

Size

2.99 KB

Version

2

Bits

09fdf627

Nonce

64,665

Timestamp

12/7/2013, 5:22:41 PM

Confirmations

6,499,873

Merkle Root

f541cfaade0f2d3ba5202de8cb0ea3be187a23af466e8889b5d4e12c5a7d9d21
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.

9.595 × 10⁹²(93-digit number)
95959129760130148352…75857022885711535679
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
9.595 × 10⁹²(93-digit number)
95959129760130148352…75857022885711535679
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
9.595 × 10⁹²(93-digit number)
95959129760130148352…75857022885711535681
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
1.919 × 10⁹³(94-digit number)
19191825952026029670…51714045771423071359
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.919 × 10⁹³(94-digit number)
19191825952026029670…51714045771423071361
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
3.838 × 10⁹³(94-digit number)
38383651904052059341…03428091542846142719
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.838 × 10⁹³(94-digit number)
38383651904052059341…03428091542846142721
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
7.676 × 10⁹³(94-digit number)
76767303808104118682…06856183085692285439
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.676 × 10⁹³(94-digit number)
76767303808104118682…06856183085692285441
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
1.535 × 10⁹⁴(95-digit number)
15353460761620823736…13712366171384570879
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:57,635,345 XPM·at block #6,798,912 · updates every 60s
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