Block #211,160

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 10/15/2013, 1:52:22 PM · Difficulty 9.9149 · 6,593,775 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
16727ab015274e01bd99e1b75a16165f195ef6998725ac3e9421ee3964a75fe3

Height

#211,160

Difficulty

9.914939

Transactions

6

Size

26.07 KB

Version

2

Bits

09ea3971

Nonce

3,587

Timestamp

10/15/2013, 1:52:22 PM

Confirmations

6,593,775

Merkle Root

b6d7e95e46d53f0884d8f2176f7fc327da673c431b3a7985361d8367ef5b316d
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.

9.113 × 10⁹²(93-digit number)
91135965606799920262…36995195017839708439
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
9.113 × 10⁹²(93-digit number)
91135965606799920262…36995195017839708439
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
9.113 × 10⁹²(93-digit number)
91135965606799920262…36995195017839708441
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
1.822 × 10⁹³(94-digit number)
18227193121359984052…73990390035679416879
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.822 × 10⁹³(94-digit number)
18227193121359984052…73990390035679416881
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
3.645 × 10⁹³(94-digit number)
36454386242719968105…47980780071358833759
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.645 × 10⁹³(94-digit number)
36454386242719968105…47980780071358833761
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
7.290 × 10⁹³(94-digit number)
72908772485439936210…95961560142717667519
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.290 × 10⁹³(94-digit number)
72908772485439936210…95961560142717667521
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
1.458 × 10⁹⁴(95-digit number)
14581754497087987242…91923120285435335039
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:57,683,554 XPM·at block #6,804,934 · updates every 60s
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