Block #83,335

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 7/26/2013, 2:12:35 AM · Difficulty 9.2676 · 6,720,196 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
6f97acaa1bd4544306a4e1578676edbf9bdc906112db2c8b36e5bb3c85a3be7a

Height

#83,335

Difficulty

9.267599

Transactions

1

Size

204 B

Version

2

Bits

09448162

Nonce

34,654

Timestamp

7/26/2013, 2:12:35 AM

Confirmations

6,720,196

Merkle Root

0824fc18325bdc3faa73fa4eb98a5cb92bd21ac72a420969df6ee3e470167151
Transactions (1)
1 in → 1 out11.6300 XPM109 B
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.

4.098 × 10¹⁰⁵(106-digit number)
40980082569382167704…83086869974210365119
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
4.098 × 10¹⁰⁵(106-digit number)
40980082569382167704…83086869974210365119
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
4.098 × 10¹⁰⁵(106-digit number)
40980082569382167704…83086869974210365121
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
8.196 × 10¹⁰⁵(106-digit number)
81960165138764335408…66173739948420730239
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
8.196 × 10¹⁰⁵(106-digit number)
81960165138764335408…66173739948420730241
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
1.639 × 10¹⁰⁶(107-digit number)
16392033027752867081…32347479896841460479
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.639 × 10¹⁰⁶(107-digit number)
16392033027752867081…32347479896841460481
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
3.278 × 10¹⁰⁶(107-digit number)
32784066055505734163…64694959793682920959
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
3.278 × 10¹⁰⁶(107-digit number)
32784066055505734163…64694959793682920961
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
6.556 × 10¹⁰⁶(107-digit number)
65568132111011468326…29389919587365841919
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:57,672,276 XPM·at block #6,803,530 · updates every 60s
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