Block #345,348

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/5/2014, 9:12:02 PM · Difficulty 10.2090 · 6,458,236 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
77e3670a8bfba6c4745e71443410f1950626ad3c30a9ae4efebf2de169b3f338

Height

#345,348

Difficulty

10.208997

Transactions

6

Size

1.45 KB

Version

2

Bits

0a3580cc

Nonce

107,052

Timestamp

1/5/2014, 9:12:02 PM

Confirmations

6,458,236

Merkle Root

675e1e1c124dbe002219808a04195615c76015a9eb5febc836e2299dbf6bb123
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.

5.078 × 10¹⁰⁰(101-digit number)
50781498606694392315…12861282517271408639
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
5.078 × 10¹⁰⁰(101-digit number)
50781498606694392315…12861282517271408639
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.078 × 10¹⁰⁰(101-digit number)
50781498606694392315…12861282517271408641
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
1.015 × 10¹⁰¹(102-digit number)
10156299721338878463…25722565034542817279
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.015 × 10¹⁰¹(102-digit number)
10156299721338878463…25722565034542817281
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
2.031 × 10¹⁰¹(102-digit number)
20312599442677756926…51445130069085634559
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.031 × 10¹⁰¹(102-digit number)
20312599442677756926…51445130069085634561
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
4.062 × 10¹⁰¹(102-digit number)
40625198885355513852…02890260138171269119
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.062 × 10¹⁰¹(102-digit number)
40625198885355513852…02890260138171269121
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
8.125 × 10¹⁰¹(102-digit number)
81250397770711027705…05780520276342538239
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.125 × 10¹⁰¹(102-digit number)
81250397770711027705…05780520276342538241
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:57,672,707 XPM·at block #6,803,583 · updates every 60s
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