Block #335,997

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/30/2013, 3:42:15 PM · Difficulty 10.1440 · 6,468,938 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
ec9269e04136f8628c713a3def21371930995e1e3ff4310a645ed8ff270093ed

Height

#335,997

Difficulty

10.143966

Transactions

9

Size

5.55 KB

Version

2

Bits

0a24daf2

Nonce

41,035

Timestamp

12/30/2013, 3:42:15 PM

Confirmations

6,468,938

Merkle Root

7cc36ac110c5591214aae6469a889417f2a536ae9fe8d2add030056039a20771
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.

7.550 × 10⁹⁷(98-digit number)
75505402978794395956…55634532948905603839
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
7.550 × 10⁹⁷(98-digit number)
75505402978794395956…55634532948905603839
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
7.550 × 10⁹⁷(98-digit number)
75505402978794395956…55634532948905603841
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
1.510 × 10⁹⁸(99-digit number)
15101080595758879191…11269065897811207679
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.510 × 10⁹⁸(99-digit number)
15101080595758879191…11269065897811207681
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
3.020 × 10⁹⁸(99-digit number)
30202161191517758382…22538131795622415359
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.020 × 10⁹⁸(99-digit number)
30202161191517758382…22538131795622415361
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
6.040 × 10⁹⁸(99-digit number)
60404322383035516764…45076263591244830719
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
6.040 × 10⁹⁸(99-digit number)
60404322383035516764…45076263591244830721
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
1.208 × 10⁹⁹(100-digit number)
12080864476607103352…90152527182489661439
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.208 × 10⁹⁹(100-digit number)
12080864476607103352…90152527182489661441
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:57,683,554 XPM·at block #6,804,934 · updates every 60s
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