Block #448,410

TWNLength 10ā˜…ā˜…ā˜†ā˜†ā˜†

Bi-Twin Chain Ā· Discovered 3/17/2014, 9:48:22 PM Ā· Difficulty 10.3679 Ā· 6,354,092 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c449b7b4e4cc6ec1a8cc9db4f41eb0e91d19593c0eb1ff9fa0e4ab63d5a194a8

Height

#448,410

Difficulty

10.367913

Transactions

3

Size

3.22 KB

Version

2

Bits

0a5e2f8b

Nonce

45,469

Timestamp

3/17/2014, 9:48:22 PM

Confirmations

6,354,092

Merkle Root

0732e846e4484189d94798ec93a503beb17e161855813f42e7c0211889cc5e4e
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.

8.719 Ɨ 10⁹⁵(96-digit number)
87193393447008642352…18112394179729855239
Discovered Prime Numbers
Lower: 2^k Ɨ origin āˆ’ 1 | Upper: 2^k Ɨ 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 āˆ’ 1
8.719 Ɨ 10⁹⁵(96-digit number)
87193393447008642352…18112394179729855239
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
8.719 Ɨ 10⁹⁵(96-digit number)
87193393447008642352…18112394179729855241
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: origin + 1 āˆ’ origin āˆ’ 1 = 2 (twin primes āœ“)
Level 1 — Twin Prime Pair (2^1 Ɨ origin ± 1)
2^1 Ɨ origin āˆ’ 1
1.743 Ɨ 10⁹⁶(97-digit number)
17438678689401728470…36224788359459710479
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 Ɨ origin + 1
1.743 Ɨ 10⁹⁶(97-digit number)
17438678689401728470…36224788359459710481
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^1 Ɨ origin + 1 āˆ’ 2^1 Ɨ origin āˆ’ 1 = 2 (twin primes āœ“)
Level 2 — Twin Prime Pair (2^2 Ɨ origin ± 1)
2^2 Ɨ origin āˆ’ 1
3.487 Ɨ 10⁹⁶(97-digit number)
34877357378803456940…72449576718919420959
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 Ɨ origin + 1
3.487 Ɨ 10⁹⁶(97-digit number)
34877357378803456940…72449576718919420961
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^2 Ɨ origin + 1 āˆ’ 2^2 Ɨ origin āˆ’ 1 = 2 (twin primes āœ“)
Level 3 — Twin Prime Pair (2^3 Ɨ origin ± 1)
2^3 Ɨ origin āˆ’ 1
6.975 Ɨ 10⁹⁶(97-digit number)
69754714757606913881…44899153437838841919
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 Ɨ origin + 1
6.975 Ɨ 10⁹⁶(97-digit number)
69754714757606913881…44899153437838841921
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^3 Ɨ origin + 1 āˆ’ 2^3 Ɨ origin āˆ’ 1 = 2 (twin primes āœ“)
Level 4 — Twin Prime Pair (2^4 Ɨ origin ± 1)
2^4 Ɨ origin āˆ’ 1
1.395 Ɨ 10⁹⁷(98-digit number)
13950942951521382776…89798306875677683839
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 Ɨ origin + 1
1.395 Ɨ 10⁹⁷(98-digit number)
13950942951521382776…89798306875677683841
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 Ɨ origin + 1 āˆ’ 2^4 Ɨ origin āˆ’ 1 = 2 (twin primes āœ“)

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.

ā˜…ā˜…ā˜†ā˜†ā˜†
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 Ɨ 3 Ɨ 5 Ɨ 7 Ɨ …), 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 Ɨ Primorial (2Ā·3Ā·5Ā·7Ā·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 āˆ’ 1 and p+2 = origin/primorial + 1
Circulating Supply:57,664,024 XPMĀ·at block #6,802,501 Ā· updates every 60s
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