Block #754,923

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 10/7/2014, 1:58:09 AM · Difficulty 10.9685 · 6,047,753 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
096bdbcb8a4f857a1526fe07af6461d56bc0d954c7899203551eb7faab57c7e7

Height

#754,923

Difficulty

10.968547

Transactions

10

Size

9.43 KB

Version

2

Bits

0af7f2b0

Nonce

331,449,191

Timestamp

10/7/2014, 1:58:09 AM

Confirmations

6,047,753

Merkle Root

413dac17ac79de0f617eed25e411b26b6c4a370f5577d81e761f2b878bf0d501
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.

6.201 × 10⁹⁶(97-digit number)
62019208993745387996…28847588515357140479
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
6.201 × 10⁹⁶(97-digit number)
62019208993745387996…28847588515357140479
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
6.201 × 10⁹⁶(97-digit number)
62019208993745387996…28847588515357140481
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
1.240 × 10⁹⁷(98-digit number)
12403841798749077599…57695177030714280959
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.240 × 10⁹⁷(98-digit number)
12403841798749077599…57695177030714280961
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
2.480 × 10⁹⁷(98-digit number)
24807683597498155198…15390354061428561919
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.480 × 10⁹⁷(98-digit number)
24807683597498155198…15390354061428561921
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
4.961 × 10⁹⁷(98-digit number)
49615367194996310397…30780708122857123839
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.961 × 10⁹⁷(98-digit number)
49615367194996310397…30780708122857123841
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
9.923 × 10⁹⁷(98-digit number)
99230734389992620794…61561416245714247679
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
9.923 × 10⁹⁷(98-digit number)
99230734389992620794…61561416245714247681
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:57,665,429 XPM·at block #6,802,675 · updates every 60s
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