Block #315,420

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/16/2013, 12:22:07 PM · Difficulty 10.0993 · 6,480,056 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c8aecada52bcce02f6272da619029e90c102df35dad83028353e9b1ad34c2f23

Height

#315,420

Difficulty

10.099268

Transactions

19

Size

5.47 KB

Version

2

Bits

0a1969a7

Nonce

204,570

Timestamp

12/16/2013, 12:22:07 PM

Confirmations

6,480,056

Merkle Root

a112237cb26805ac5846171331cefe994a26156647d289e4d0541dcd81165751
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.

5.956 × 10⁹⁷(98-digit number)
59562191944064940536…45750183549724083359
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
5.956 × 10⁹⁷(98-digit number)
59562191944064940536…45750183549724083359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.956 × 10⁹⁷(98-digit number)
59562191944064940536…45750183549724083361
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
1.191 × 10⁹⁸(99-digit number)
11912438388812988107…91500367099448166719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.191 × 10⁹⁸(99-digit number)
11912438388812988107…91500367099448166721
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
2.382 × 10⁹⁸(99-digit number)
23824876777625976214…83000734198896333439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.382 × 10⁹⁸(99-digit number)
23824876777625976214…83000734198896333441
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
4.764 × 10⁹⁸(99-digit number)
47649753555251952429…66001468397792666879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.764 × 10⁹⁸(99-digit number)
47649753555251952429…66001468397792666881
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
9.529 × 10⁹⁸(99-digit number)
95299507110503904858…32002936795585333759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
9.529 × 10⁹⁸(99-digit number)
95299507110503904858…32002936795585333761
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:57,607,869 XPM·at block #6,795,475 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.