Block #1,054,661

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 5/11/2015, 12:17:07 PM · Difficulty 10.7278 · 5,741,221 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
7361e09c176ae80b62609ba3fa73db1a78f0b7989c538a3aee467e715d3dba7c

Height

#1,054,661

Difficulty

10.727836

Transactions

4

Size

1.29 KB

Version

2

Bits

0aba5376

Nonce

1,518,856,548

Timestamp

5/11/2015, 12:17:07 PM

Confirmations

5,741,221

Merkle Root

15c306547f7e88714ab6684eba173eebe859438f91ae095989a832c66bc4772a
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.

1.662 × 10⁹⁸(99-digit number)
16626631738307355896…32783407677873971199
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
1.662 × 10⁹⁸(99-digit number)
16626631738307355896…32783407677873971199
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.662 × 10⁹⁸(99-digit number)
16626631738307355896…32783407677873971201
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
3.325 × 10⁹⁸(99-digit number)
33253263476614711792…65566815355747942399
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
3.325 × 10⁹⁸(99-digit number)
33253263476614711792…65566815355747942401
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
6.650 × 10⁹⁸(99-digit number)
66506526953229423585…31133630711495884799
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
6.650 × 10⁹⁸(99-digit number)
66506526953229423585…31133630711495884801
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
1.330 × 10⁹⁹(100-digit number)
13301305390645884717…62267261422991769599
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.330 × 10⁹⁹(100-digit number)
13301305390645884717…62267261422991769601
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
2.660 × 10⁹⁹(100-digit number)
26602610781291769434…24534522845983539199
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.660 × 10⁹⁹(100-digit number)
26602610781291769434…24534522845983539201
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:57,611,146 XPM·at block #6,795,881 · updates every 60s
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