Block #322,873

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/21/2013, 7:38:39 AM · Difficulty 10.1929 · 6,473,613 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
f5ce760508fa62e500f5ebec00806aa5d3d11e37e9eb4e644f8f87696620ef0c

Height

#322,873

Difficulty

10.192939

Transactions

20

Size

25.36 KB

Version

2

Bits

0a31646b

Nonce

29,745

Timestamp

12/21/2013, 7:38:39 AM

Confirmations

6,473,613

Merkle Root

60bc5d49c9105862fd8e42eb43080d0e0f774fe2ab0308c2e1e0f56ff2cfd162
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.

3.935 × 10⁹⁴(95-digit number)
39351559860066887444…89631009059515673599
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
3.935 × 10⁹⁴(95-digit number)
39351559860066887444…89631009059515673599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.935 × 10⁹⁴(95-digit number)
39351559860066887444…89631009059515673601
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
7.870 × 10⁹⁴(95-digit number)
78703119720133774888…79262018119031347199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.870 × 10⁹⁴(95-digit number)
78703119720133774888…79262018119031347201
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
1.574 × 10⁹⁵(96-digit number)
15740623944026754977…58524036238062694399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.574 × 10⁹⁵(96-digit number)
15740623944026754977…58524036238062694401
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
3.148 × 10⁹⁵(96-digit number)
31481247888053509955…17048072476125388799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.148 × 10⁹⁵(96-digit number)
31481247888053509955…17048072476125388801
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
6.296 × 10⁹⁵(96-digit number)
62962495776107019910…34096144952250777599
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
6.296 × 10⁹⁵(96-digit number)
62962495776107019910…34096144952250777601
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:57,615,886 XPM·at block #6,796,485 · 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.