Block #270,166

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/23/2013, 6:13:31 PM · Difficulty 9.9518 · 6,521,642 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c19933c966625fcfe23cfe200be8273c83309d5f43c6cd36c4a2e13ca480edac

Height

#270,166

Difficulty

9.951801

Transactions

7

Size

1.95 KB

Version

2

Bits

09f3a93b

Nonce

34,475

Timestamp

11/23/2013, 6:13:31 PM

Confirmations

6,521,642

Merkle Root

e662179a1a1e440e1d8a28cb488d36562e28c590469c00d9c3a6c6388683d28b
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.

1.373 × 10⁹³(94-digit number)
13735920710771202489…37622323276221098879
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
1.373 × 10⁹³(94-digit number)
13735920710771202489…37622323276221098879
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.373 × 10⁹³(94-digit number)
13735920710771202489…37622323276221098881
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
2.747 × 10⁹³(94-digit number)
27471841421542404979…75244646552442197759
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.747 × 10⁹³(94-digit number)
27471841421542404979…75244646552442197761
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
5.494 × 10⁹³(94-digit number)
54943682843084809959…50489293104884395519
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.494 × 10⁹³(94-digit number)
54943682843084809959…50489293104884395521
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
1.098 × 10⁹⁴(95-digit number)
10988736568616961991…00978586209768791039
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.098 × 10⁹⁴(95-digit number)
10988736568616961991…00978586209768791041
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
2.197 × 10⁹⁴(95-digit number)
21977473137233923983…01957172419537582079
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:57,578,409 XPM·at block #6,791,807 · updates every 60s
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