Block #310,935

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/14/2013, 7:49:58 AM · Difficulty 9.9953 · 6,488,212 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
b33021a9c511e9954d02290be0a8b78070e0317e3f0fd09321f3ace07b727775

Height

#310,935

Difficulty

9.995331

Transactions

9

Size

4.24 KB

Version

2

Bits

09fecdff

Nonce

138,186

Timestamp

12/14/2013, 7:49:58 AM

Confirmations

6,488,212

Merkle Root

e8818a3952320458fc123303b9719fd87155a2c9ea171c4fe424160f4f74888c
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.

2.983 × 10⁹³(94-digit number)
29835412703848782250…52721554666407715839
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
2.983 × 10⁹³(94-digit number)
29835412703848782250…52721554666407715839
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.983 × 10⁹³(94-digit number)
29835412703848782250…52721554666407715841
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
5.967 × 10⁹³(94-digit number)
59670825407697564501…05443109332815431679
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.967 × 10⁹³(94-digit number)
59670825407697564501…05443109332815431681
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
1.193 × 10⁹⁴(95-digit number)
11934165081539512900…10886218665630863359
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.193 × 10⁹⁴(95-digit number)
11934165081539512900…10886218665630863361
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
2.386 × 10⁹⁴(95-digit number)
23868330163079025800…21772437331261726719
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.386 × 10⁹⁴(95-digit number)
23868330163079025800…21772437331261726721
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
4.773 × 10⁹⁴(95-digit number)
47736660326158051600…43544874662523453439
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.773 × 10⁹⁴(95-digit number)
47736660326158051600…43544874662523453441
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:57,637,212 XPM·at block #6,799,146 · updates every 60s
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