Block #150,152

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 9/4/2013, 8:14:42 PM · Difficulty 9.8586 · 6,652,657 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
af0da7818a4b2da2b83113386ffdd851ccbe169597dd702b4c2ced64813971de

Height

#150,152

Difficulty

9.858586

Transactions

9

Size

4.14 KB

Version

2

Bits

09dbcc52

Nonce

4,144

Timestamp

9/4/2013, 8:14:42 PM

Confirmations

6,652,657

Merkle Root

5b7b90736abbc6829ffe0f1214ac0a701ebfb5956eef6bbc7d681d46fff165e3
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.

9.436 × 10⁹¹(92-digit number)
94366815795576955806…15573113014573742319
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
9.436 × 10⁹¹(92-digit number)
94366815795576955806…15573113014573742319
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
9.436 × 10⁹¹(92-digit number)
94366815795576955806…15573113014573742321
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
1.887 × 10⁹²(93-digit number)
18873363159115391161…31146226029147484639
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.887 × 10⁹²(93-digit number)
18873363159115391161…31146226029147484641
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
3.774 × 10⁹²(93-digit number)
37746726318230782322…62292452058294969279
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.774 × 10⁹²(93-digit number)
37746726318230782322…62292452058294969281
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
7.549 × 10⁹²(93-digit number)
75493452636461564645…24584904116589938559
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.549 × 10⁹²(93-digit number)
75493452636461564645…24584904116589938561
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
1.509 × 10⁹³(94-digit number)
15098690527292312929…49169808233179877119
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:57,666,501 XPM·at block #6,802,808 · updates every 60s
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