Block #301,041

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 12/8/2013, 10:40:42 PM · Difficulty 9.9925 · 6,498,268 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
73c6d2e41c07eb1ec19ccaf3914acf87fc350533311e549cb5e5cb8b0119c3fb

Height

#301,041

Difficulty

9.992476

Transactions

33

Size

10.61 KB

Version

2

Bits

09fe12ed

Nonce

55,938

Timestamp

12/8/2013, 10:40:42 PM

Confirmations

6,498,268

Merkle Root

7c2c4d1faef8da71ede3b64a6e41237f4b07b855cdef892db2bfb5455a2e53f0
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.

9.584 × 10⁹⁵(96-digit number)
95841667358465001783…44890406103663088639
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
9.584 × 10⁹⁵(96-digit number)
95841667358465001783…44890406103663088639
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
9.584 × 10⁹⁵(96-digit number)
95841667358465001783…44890406103663088641
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
1.916 × 10⁹⁶(97-digit number)
19168333471693000356…89780812207326177279
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.916 × 10⁹⁶(97-digit number)
19168333471693000356…89780812207326177281
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
3.833 × 10⁹⁶(97-digit number)
38336666943386000713…79561624414652354559
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.833 × 10⁹⁶(97-digit number)
38336666943386000713…79561624414652354561
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
7.667 × 10⁹⁶(97-digit number)
76673333886772001426…59123248829304709119
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.667 × 10⁹⁶(97-digit number)
76673333886772001426…59123248829304709121
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
1.533 × 10⁹⁷(98-digit number)
15334666777354400285…18246497658609418239
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:57,638,518 XPM·at block #6,799,308 · updates every 60s
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