Block #411,563

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/19/2014, 8:58:19 PM · Difficulty 10.4267 · 6,393,797 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
755b2bb0dd82026a4a4293fca34ff80f6823daa7d09f870cd0ddd8516f19f82d

Height

#411,563

Difficulty

10.426717

Transactions

5

Size

2.29 KB

Version

2

Bits

0a6d3d4c

Nonce

1,991

Timestamp

2/19/2014, 8:58:19 PM

Confirmations

6,393,797

Merkle Root

df62044d98fde16c458ba91397c06718b6fb454fdb23b7790a7d51764b460853
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.

3.995 × 10⁹⁷(98-digit number)
39954639993279866090…33041522457337838949
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
3.995 × 10⁹⁷(98-digit number)
39954639993279866090…33041522457337838949
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.995 × 10⁹⁷(98-digit number)
39954639993279866090…33041522457337838951
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
7.990 × 10⁹⁷(98-digit number)
79909279986559732181…66083044914675677899
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.990 × 10⁹⁷(98-digit number)
79909279986559732181…66083044914675677901
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
1.598 × 10⁹⁸(99-digit number)
15981855997311946436…32166089829351355799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.598 × 10⁹⁸(99-digit number)
15981855997311946436…32166089829351355801
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
3.196 × 10⁹⁸(99-digit number)
31963711994623892872…64332179658702711599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.196 × 10⁹⁸(99-digit number)
31963711994623892872…64332179658702711601
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
6.392 × 10⁹⁸(99-digit number)
63927423989247785745…28664359317405423199
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
6.392 × 10⁹⁸(99-digit number)
63927423989247785745…28664359317405423201
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:57,686,953 XPM·at block #6,805,359 · updates every 60s
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