Block #316,398

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/17/2013, 1:23:55 AM · Difficulty 10.1335 · 6,478,045 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c561c723e5c25fc68939fa3b4b1f5d0b7855dd27cd0e02f53d7bdabeb6969645

Height

#316,398

Difficulty

10.133548

Transactions

1

Size

1.05 KB

Version

2

Bits

0a223033

Nonce

3,634

Timestamp

12/17/2013, 1:23:55 AM

Confirmations

6,478,045

Merkle Root

e65d79f4d4c1c4db19183eb4d11a962016455af72e976a35a478136417c0940a
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.

2.067 × 10¹⁰¹(102-digit number)
20674621832377323306…78052797506863922879
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
2.067 × 10¹⁰¹(102-digit number)
20674621832377323306…78052797506863922879
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.067 × 10¹⁰¹(102-digit number)
20674621832377323306…78052797506863922881
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
4.134 × 10¹⁰¹(102-digit number)
41349243664754646612…56105595013727845759
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.134 × 10¹⁰¹(102-digit number)
41349243664754646612…56105595013727845761
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
8.269 × 10¹⁰¹(102-digit number)
82698487329509293225…12211190027455691519
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
8.269 × 10¹⁰¹(102-digit number)
82698487329509293225…12211190027455691521
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
1.653 × 10¹⁰²(103-digit number)
16539697465901858645…24422380054911383039
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.653 × 10¹⁰²(103-digit number)
16539697465901858645…24422380054911383041
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
3.307 × 10¹⁰²(103-digit number)
33079394931803717290…48844760109822766079
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.307 × 10¹⁰²(103-digit number)
33079394931803717290…48844760109822766081
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:57,599,582 XPM·at block #6,794,442 · 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.