Block #352,400

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/10/2014, 7:46:37 AM · Difficulty 10.3073 · 6,452,961 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
51b37eb8652f231e37b1c1d21bbe811ba83a9bdccfe4db4e67d197f0deb1a890

Height

#352,400

Difficulty

10.307281

Transactions

5

Size

2.93 KB

Version

2

Bits

0a4ea9fa

Nonce

140,497

Timestamp

1/10/2014, 7:46:37 AM

Confirmations

6,452,961

Merkle Root

9ddf2e0f2d00365d9d7db12ee9a612cadc0daefc3ed807357cd8af83b18ce0b4
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.

1.661 × 10¹⁰¹(102-digit number)
16611618024104075504…87287229286423859199
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
1.661 × 10¹⁰¹(102-digit number)
16611618024104075504…87287229286423859199
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.661 × 10¹⁰¹(102-digit number)
16611618024104075504…87287229286423859201
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
3.322 × 10¹⁰¹(102-digit number)
33223236048208151009…74574458572847718399
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.322 × 10¹⁰¹(102-digit number)
33223236048208151009…74574458572847718401
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
6.644 × 10¹⁰¹(102-digit number)
66446472096416302018…49148917145695436799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
6.644 × 10¹⁰¹(102-digit number)
66446472096416302018…49148917145695436801
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
1.328 × 10¹⁰²(103-digit number)
13289294419283260403…98297834291390873599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.328 × 10¹⁰²(103-digit number)
13289294419283260403…98297834291390873601
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
2.657 × 10¹⁰²(103-digit number)
26578588838566520807…96595668582781747199
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.657 × 10¹⁰²(103-digit number)
26578588838566520807…96595668582781747201
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:57,686,961 XPM·at block #6,805,360 · updates every 60s
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