Block #650,827

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 7/27/2014, 9:06:29 PM · Difficulty 10.9529 · 6,148,208 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
555de4f926ae8c34ab7a2654ad93baf65641e9b0ceca42857ba1fc048528c1b9

Height

#650,827

Difficulty

10.952930

Transactions

7

Size

1.96 KB

Version

2

Bits

0af3f338

Nonce

2,601,476,033

Timestamp

7/27/2014, 9:06:29 PM

Confirmations

6,148,208

Merkle Root

2a4e8c4dbc922f0d09003949ab1d6f4102cbb1801d9ef6f6c76774d175466c12
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.

1.009 × 10⁹⁵(96-digit number)
10094159492962163355…56137242169421809379
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
1.009 × 10⁹⁵(96-digit number)
10094159492962163355…56137242169421809379
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.009 × 10⁹⁵(96-digit number)
10094159492962163355…56137242169421809381
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
2.018 × 10⁹⁵(96-digit number)
20188318985924326711…12274484338843618759
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.018 × 10⁹⁵(96-digit number)
20188318985924326711…12274484338843618761
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
4.037 × 10⁹⁵(96-digit number)
40376637971848653423…24548968677687237519
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.037 × 10⁹⁵(96-digit number)
40376637971848653423…24548968677687237521
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
8.075 × 10⁹⁵(96-digit number)
80753275943697306846…49097937355374475039
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.075 × 10⁹⁵(96-digit number)
80753275943697306846…49097937355374475041
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
1.615 × 10⁹⁶(97-digit number)
16150655188739461369…98195874710748950079
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.615 × 10⁹⁶(97-digit number)
16150655188739461369…98195874710748950081
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:57,636,319 XPM·at block #6,799,034 · updates every 60s
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