Block #321,610

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/20/2013, 10:30:06 AM · Difficulty 10.1929 · 6,481,709 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
7124badf12979c0e7cbd38748c5242ba5179089b658404007a1e858295fc491f

Height

#321,610

Difficulty

10.192919

Transactions

10

Size

5.80 KB

Version

2

Bits

0a316329

Nonce

4,338

Timestamp

12/20/2013, 10:30:06 AM

Confirmations

6,481,709

Merkle Root

c9f9bf966cac9a6f64da90127c955fa42643849b77e7c11e279509b6024480e4
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.

1.369 × 10¹⁰⁰(101-digit number)
13692289889416491698…60064327924095130719
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
1.369 × 10¹⁰⁰(101-digit number)
13692289889416491698…60064327924095130719
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.369 × 10¹⁰⁰(101-digit number)
13692289889416491698…60064327924095130721
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
2.738 × 10¹⁰⁰(101-digit number)
27384579778832983396…20128655848190261439
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.738 × 10¹⁰⁰(101-digit number)
27384579778832983396…20128655848190261441
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
5.476 × 10¹⁰⁰(101-digit number)
54769159557665966793…40257311696380522879
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.476 × 10¹⁰⁰(101-digit number)
54769159557665966793…40257311696380522881
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
1.095 × 10¹⁰¹(102-digit number)
10953831911533193358…80514623392761045759
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.095 × 10¹⁰¹(102-digit number)
10953831911533193358…80514623392761045761
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
2.190 × 10¹⁰¹(102-digit number)
21907663823066386717…61029246785522091519
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.190 × 10¹⁰¹(102-digit number)
21907663823066386717…61029246785522091521
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:57,670,581 XPM·at block #6,803,318 · updates every 60s
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