Block #350,455

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/9/2014, 1:37:35 AM · Difficulty 10.2876 · 6,455,315 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
f66a7c5774177cd964861899e661bb966fae3224fc49dbf7510fbf1d58e39c7e

Height

#350,455

Difficulty

10.287608

Transactions

6

Size

1.76 KB

Version

2

Bits

0a49a0b4

Nonce

70,581

Timestamp

1/9/2014, 1:37:35 AM

Confirmations

6,455,315

Merkle Root

dabaeb576eff431a6d9c86a48ef21fd693cd5c4fe73a759b7617b6b9fc4f3c6b
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.

2.225 × 10⁹⁹(100-digit number)
22257745449714044628…59650466346345902079
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
2.225 × 10⁹⁹(100-digit number)
22257745449714044628…59650466346345902079
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.225 × 10⁹⁹(100-digit number)
22257745449714044628…59650466346345902081
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
4.451 × 10⁹⁹(100-digit number)
44515490899428089257…19300932692691804159
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.451 × 10⁹⁹(100-digit number)
44515490899428089257…19300932692691804161
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
8.903 × 10⁹⁹(100-digit number)
89030981798856178514…38601865385383608319
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
8.903 × 10⁹⁹(100-digit number)
89030981798856178514…38601865385383608321
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
1.780 × 10¹⁰⁰(101-digit number)
17806196359771235702…77203730770767216639
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.780 × 10¹⁰⁰(101-digit number)
17806196359771235702…77203730770767216641
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
3.561 × 10¹⁰⁰(101-digit number)
35612392719542471405…54407461541534433279
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.561 × 10¹⁰⁰(101-digit number)
35612392719542471405…54407461541534433281
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:57,690,244 XPM·at block #6,805,769 · updates every 60s
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