Block #317,477

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/17/2013, 5:52:42 PM · Difficulty 10.1493 · 6,485,075 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
5e8e80bf485428edf87e0e85c328810573c128e2a026c7e3da495c9b951c8d58

Height

#317,477

Difficulty

10.149301

Transactions

6

Size

1.88 KB

Version

2

Bits

0a263897

Nonce

141,984

Timestamp

12/17/2013, 5:52:42 PM

Confirmations

6,485,075

Merkle Root

af810011d22a028f5fed6899fc37a3bff010ff940765c9e7918666767b5ef808
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.

5.073 × 10⁹⁷(98-digit number)
50733705903767833376…28588501777820057599
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
5.073 × 10⁹⁷(98-digit number)
50733705903767833376…28588501777820057599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.073 × 10⁹⁷(98-digit number)
50733705903767833376…28588501777820057601
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
1.014 × 10⁹⁸(99-digit number)
10146741180753566675…57177003555640115199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.014 × 10⁹⁸(99-digit number)
10146741180753566675…57177003555640115201
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
2.029 × 10⁹⁸(99-digit number)
20293482361507133350…14354007111280230399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.029 × 10⁹⁸(99-digit number)
20293482361507133350…14354007111280230401
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
4.058 × 10⁹⁸(99-digit number)
40586964723014266700…28708014222560460799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.058 × 10⁹⁸(99-digit number)
40586964723014266700…28708014222560460801
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
8.117 × 10⁹⁸(99-digit number)
81173929446028533401…57416028445120921599
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.117 × 10⁹⁸(99-digit number)
81173929446028533401…57416028445120921601
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:57,664,429 XPM·at block #6,802,551 · updates every 60s
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