Block #989,368

TWNLength 11★★★☆☆

Bi-Twin Chain · Discovered 3/24/2015, 11:35:33 PM · Difficulty 10.8529 · 5,813,427 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
260b2172893d63607c2d07f36e4542578da08870f2b50522323499a2e443786d

Height

#989,368

Difficulty

10.852938

Transactions

4

Size

4.11 KB

Version

2

Bits

0ada5a2a

Nonce

43,371,363

Timestamp

3/24/2015, 11:35:33 PM

Confirmations

5,813,427

Merkle Root

1af99cb305cf1b47b02a9be51829c42a9c8831423aaf7da01d35ad315f0f66c1
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.

1.692 × 10⁹⁵(96-digit number)
16927757474244934180…53551112854879109119
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
1.692 × 10⁹⁵(96-digit number)
16927757474244934180…53551112854879109119
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.692 × 10⁹⁵(96-digit number)
16927757474244934180…53551112854879109121
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
3.385 × 10⁹⁵(96-digit number)
33855514948489868361…07102225709758218239
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.385 × 10⁹⁵(96-digit number)
33855514948489868361…07102225709758218241
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
6.771 × 10⁹⁵(96-digit number)
67711029896979736723…14204451419516436479
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
6.771 × 10⁹⁵(96-digit number)
67711029896979736723…14204451419516436481
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
1.354 × 10⁹⁶(97-digit number)
13542205979395947344…28408902839032872959
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.354 × 10⁹⁶(97-digit number)
13542205979395947344…28408902839032872961
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
2.708 × 10⁹⁶(97-digit number)
27084411958791894689…56817805678065745919
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.708 × 10⁹⁶(97-digit number)
27084411958791894689…56817805678065745921
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)
Level 5 — Twin Prime Pair (2^5 × origin ± 1)
2^5 × origin − 1
5.416 × 10⁹⁶(97-digit number)
54168823917583789378…13635611356131491839
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,666,387 XPM·at block #6,802,794 · 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.