Block #461,120

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/26/2014, 12:12:30 PM · Difficulty 10.4161 · 6,338,368 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
17532a751f670907211e60fcbd73e38966cde236af7a35a95d738f55a2f3d499

Height

#461,120

Difficulty

10.416098

Transactions

6

Size

1.95 KB

Version

2

Bits

0a6a856e

Nonce

15,249

Timestamp

3/26/2014, 12:12:30 PM

Confirmations

6,338,368

Merkle Root

c8315e1c288b91dbe25119411e6218c96fa21b5a101ac4c4283b3b44a124ebc6
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.

1.345 × 10⁹⁸(99-digit number)
13456554778283080410…24613908465251274159
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
1.345 × 10⁹⁸(99-digit number)
13456554778283080410…24613908465251274159
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.345 × 10⁹⁸(99-digit number)
13456554778283080410…24613908465251274161
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
2.691 × 10⁹⁸(99-digit number)
26913109556566160821…49227816930502548319
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.691 × 10⁹⁸(99-digit number)
26913109556566160821…49227816930502548321
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
5.382 × 10⁹⁸(99-digit number)
53826219113132321643…98455633861005096639
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.382 × 10⁹⁸(99-digit number)
53826219113132321643…98455633861005096641
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
1.076 × 10⁹⁹(100-digit number)
10765243822626464328…96911267722010193279
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.076 × 10⁹⁹(100-digit number)
10765243822626464328…96911267722010193281
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
2.153 × 10⁹⁹(100-digit number)
21530487645252928657…93822535444020386559
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.153 × 10⁹⁹(100-digit number)
21530487645252928657…93822535444020386561
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:57,639,947 XPM·at block #6,799,487 · updates every 60s
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