Block #378,131

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/27/2014, 2:34:15 PM · Difficulty 10.4230 · 6,420,803 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
d36141ddb307d488b0d0bc70c90aa48c09e2f549ff7e0e9b0439862558331394

Height

#378,131

Difficulty

10.423016

Transactions

5

Size

1.05 KB

Version

2

Bits

0a6c4ac3

Nonce

101,018

Timestamp

1/27/2014, 2:34:15 PM

Confirmations

6,420,803

Merkle Root

46186445d999f346c0ca207374305c7d28cc6577a50eea1e1fe7eb47cdb2a0ec
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.

2.907 × 10¹⁰¹(102-digit number)
29078813004057173878…76370561853129743359
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
2.907 × 10¹⁰¹(102-digit number)
29078813004057173878…76370561853129743359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.907 × 10¹⁰¹(102-digit number)
29078813004057173878…76370561853129743361
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
5.815 × 10¹⁰¹(102-digit number)
58157626008114347757…52741123706259486719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.815 × 10¹⁰¹(102-digit number)
58157626008114347757…52741123706259486721
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
1.163 × 10¹⁰²(103-digit number)
11631525201622869551…05482247412518973439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.163 × 10¹⁰²(103-digit number)
11631525201622869551…05482247412518973441
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
2.326 × 10¹⁰²(103-digit number)
23263050403245739103…10964494825037946879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.326 × 10¹⁰²(103-digit number)
23263050403245739103…10964494825037946881
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
4.652 × 10¹⁰²(103-digit number)
46526100806491478206…21928989650075893759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.652 × 10¹⁰²(103-digit number)
46526100806491478206…21928989650075893761
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:57,635,507 XPM·at block #6,798,933 · updates every 60s
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