Block #272,110

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/25/2013, 1:33:12 AM · Difficulty 9.9525 · 6,531,193 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
e4d865300907789d5357e6d7f701d9cf8ca1c64f24bfd6ab6aa7d1a1ca7d3cd9

Height

#272,110

Difficulty

9.952523

Transactions

6

Size

2.02 KB

Version

2

Bits

09f3d88d

Nonce

138,165

Timestamp

11/25/2013, 1:33:12 AM

Confirmations

6,531,193

Merkle Root

022d6b077d7c196a460fb135414e95dd5d6064f86625775200341c809b778364
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.

3.177 × 10⁹³(94-digit number)
31776959349679117324…86563595125888342399
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
3.177 × 10⁹³(94-digit number)
31776959349679117324…86563595125888342399
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.177 × 10⁹³(94-digit number)
31776959349679117324…86563595125888342401
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
6.355 × 10⁹³(94-digit number)
63553918699358234649…73127190251776684799
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.355 × 10⁹³(94-digit number)
63553918699358234649…73127190251776684801
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
1.271 × 10⁹⁴(95-digit number)
12710783739871646929…46254380503553369599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.271 × 10⁹⁴(95-digit number)
12710783739871646929…46254380503553369601
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
2.542 × 10⁹⁴(95-digit number)
25421567479743293859…92508761007106739199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.542 × 10⁹⁴(95-digit number)
25421567479743293859…92508761007106739201
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
5.084 × 10⁹⁴(95-digit number)
50843134959486587719…85017522014213478399
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,670,451 XPM·at block #6,803,302 · updates every 60s
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