Block #294,564

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/4/2013, 10:50:50 PM · Difficulty 9.9911 · 6,508,890 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
4b4188bd7de43f78e5ac371a570e65c0891236d972bd189922dac11feafcd438

Height

#294,564

Difficulty

9.991077

Transactions

8

Size

4.50 KB

Version

2

Bits

09fdb731

Nonce

21,767

Timestamp

12/4/2013, 10:50:50 PM

Confirmations

6,508,890

Merkle Root

72ee44b37079f177904a1f158d247026a968d8684e8e22092f06271c471e5f3e
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.

2.473 × 10⁹⁴(95-digit number)
24731083302235399028…69091926593536144799
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
2.473 × 10⁹⁴(95-digit number)
24731083302235399028…69091926593536144799
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.473 × 10⁹⁴(95-digit number)
24731083302235399028…69091926593536144801
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
4.946 × 10⁹⁴(95-digit number)
49462166604470798056…38183853187072289599
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.946 × 10⁹⁴(95-digit number)
49462166604470798056…38183853187072289601
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
9.892 × 10⁹⁴(95-digit number)
98924333208941596113…76367706374144579199
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
9.892 × 10⁹⁴(95-digit number)
98924333208941596113…76367706374144579201
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
1.978 × 10⁹⁵(96-digit number)
19784866641788319222…52735412748289158399
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.978 × 10⁹⁵(96-digit number)
19784866641788319222…52735412748289158401
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
3.956 × 10⁹⁵(96-digit number)
39569733283576638445…05470825496578316799
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.956 × 10⁹⁵(96-digit number)
39569733283576638445…05470825496578316801
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:57,671,659 XPM·at block #6,803,453 · updates every 60s
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