Block #286,612

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/30/2013, 11:27:13 PM · Difficulty 9.9858 · 6,509,369 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
77f2380b413bf60c44b55f0a9f59b83377df1e8f671fe1217de83b2090954981

Height

#286,612

Difficulty

9.985780

Transactions

11

Size

4.59 KB

Version

2

Bits

09fc5c1a

Nonce

38,021

Timestamp

11/30/2013, 11:27:13 PM

Confirmations

6,509,369

Merkle Root

62cb14f7e1bb0bda95f7f6c4830fe167db9410188d35248a35180d18b6055389
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.

1.146 × 10¹⁰³(104-digit number)
11460730910973695867…43760141976788388079
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
1.146 × 10¹⁰³(104-digit number)
11460730910973695867…43760141976788388079
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.146 × 10¹⁰³(104-digit number)
11460730910973695867…43760141976788388081
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
2.292 × 10¹⁰³(104-digit number)
22921461821947391734…87520283953576776159
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.292 × 10¹⁰³(104-digit number)
22921461821947391734…87520283953576776161
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
4.584 × 10¹⁰³(104-digit number)
45842923643894783468…75040567907153552319
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.584 × 10¹⁰³(104-digit number)
45842923643894783468…75040567907153552321
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
9.168 × 10¹⁰³(104-digit number)
91685847287789566937…50081135814307104639
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
9.168 × 10¹⁰³(104-digit number)
91685847287789566937…50081135814307104641
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
1.833 × 10¹⁰⁴(105-digit number)
18337169457557913387…00162271628614209279
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:57,611,942 XPM·at block #6,795,980 · updates every 60s
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