Block #486,727

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/11/2014, 6:12:25 PM · Difficulty 10.6309 · 6,317,299 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
449ed3c67ccc1e2eabba3fba6db55e95ddf8e4e51d76887fd53f09aa4f0fa090

Height

#486,727

Difficulty

10.630898

Transactions

7

Size

1.96 KB

Version

2

Bits

0aa18288

Nonce

351,273,103

Timestamp

4/11/2014, 6:12:25 PM

Confirmations

6,317,299

Merkle Root

3de9bb5b594f871addd83f7bda5ad36ee844f65dac56e240a2cd56c3fb63ce9c
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.

1.607 × 10⁹⁷(98-digit number)
16075047648090362091…17550946624542780719
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
1.607 × 10⁹⁷(98-digit number)
16075047648090362091…17550946624542780719
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.607 × 10⁹⁷(98-digit number)
16075047648090362091…17550946624542780721
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
3.215 × 10⁹⁷(98-digit number)
32150095296180724182…35101893249085561439
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.215 × 10⁹⁷(98-digit number)
32150095296180724182…35101893249085561441
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
6.430 × 10⁹⁷(98-digit number)
64300190592361448364…70203786498171122879
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
6.430 × 10⁹⁷(98-digit number)
64300190592361448364…70203786498171122881
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
1.286 × 10⁹⁸(99-digit number)
12860038118472289672…40407572996342245759
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.286 × 10⁹⁸(99-digit number)
12860038118472289672…40407572996342245761
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
2.572 × 10⁹⁸(99-digit number)
25720076236944579345…80815145992684491519
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.572 × 10⁹⁸(99-digit number)
25720076236944579345…80815145992684491521
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:57,676,259 XPM·at block #6,804,025 · updates every 60s
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