Block #270,108

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 11/23/2013, 5:08:43 PM · Difficulty 9.9519 · 6,529,261 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
e46dc2250bc137304ef644098dac6775e4cd65d2d52e354ee473c4c93c0b988c

Height

#270,108

Difficulty

9.951868

Transactions

6

Size

1.55 KB

Version

2

Bits

09f3ad97

Nonce

110,002

Timestamp

11/23/2013, 5:08:43 PM

Confirmations

6,529,261

Merkle Root

299fd66890597edafc457903e9492471cdfad7470301ff1b9d4d3f1b64f336bc
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.

3.688 × 10⁹⁴(95-digit number)
36886806205507993026…33886356737818623999
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
3.688 × 10⁹⁴(95-digit number)
36886806205507993026…33886356737818623999
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.688 × 10⁹⁴(95-digit number)
36886806205507993026…33886356737818624001
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
7.377 × 10⁹⁴(95-digit number)
73773612411015986052…67772713475637247999
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.377 × 10⁹⁴(95-digit number)
73773612411015986052…67772713475637248001
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
1.475 × 10⁹⁵(96-digit number)
14754722482203197210…35545426951274495999
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.475 × 10⁹⁵(96-digit number)
14754722482203197210…35545426951274496001
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
2.950 × 10⁹⁵(96-digit number)
29509444964406394421…71090853902548991999
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.950 × 10⁹⁵(96-digit number)
29509444964406394421…71090853902548992001
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
5.901 × 10⁹⁵(96-digit number)
59018889928812788842…42181707805097983999
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:57,639,000 XPM·at block #6,799,368 · updates every 60s
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