Block #469,554

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/1/2014, 7:46:19 AM · Difficulty 10.4274 · 6,335,645 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c266d13af8f8916dc8db8d62516a9a24f038c667ee8051572aed7fafa9be46c0

Height

#469,554

Difficulty

10.427384

Transactions

2

Size

976 B

Version

2

Bits

0a6d6904

Nonce

8,582

Timestamp

4/1/2014, 7:46:19 AM

Confirmations

6,335,645

Merkle Root

ac4cb3ceb11b9bcb0729ae0d4aedf6e2ae39aecbac9221d5d2c4137e21a82d06
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.

1.315 × 10⁹⁸(99-digit number)
13153412477811146954…03689012398496666359
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
1.315 × 10⁹⁸(99-digit number)
13153412477811146954…03689012398496666359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.315 × 10⁹⁸(99-digit number)
13153412477811146954…03689012398496666361
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
2.630 × 10⁹⁸(99-digit number)
26306824955622293909…07378024796993332719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.630 × 10⁹⁸(99-digit number)
26306824955622293909…07378024796993332721
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
5.261 × 10⁹⁸(99-digit number)
52613649911244587818…14756049593986665439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.261 × 10⁹⁸(99-digit number)
52613649911244587818…14756049593986665441
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
1.052 × 10⁹⁹(100-digit number)
10522729982248917563…29512099187973330879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.052 × 10⁹⁹(100-digit number)
10522729982248917563…29512099187973330881
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
2.104 × 10⁹⁹(100-digit number)
21045459964497835127…59024198375946661759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.104 × 10⁹⁹(100-digit number)
21045459964497835127…59024198375946661761
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:57,685,662 XPM·at block #6,805,198 · updates every 60s
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