Home/Chain Registry/Block #857,452

Block #857,452

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 12/17/2014, 8:37:13 PM · Difficulty 10.9675 · 5,985,031 confirmations

1CC
Cunningham Chain of the First Kind

A sequence where each prime is double the previous prime plus one.

Block Header
Block Hash
195eacbcc89fc7d245a4c22c67974b4bbd5356d36614b66d4398e840470590fc

Height

#857,452

Difficulty

10.967520

Transactions

12

Size

3.35 KB

Version

2

Bits

0af7af5d

Nonce

2,065,818,082

Timestamp

12/17/2014, 8:37:13 PM

Confirmations

5,985,031

Merkle Root

f476f140ae8575ffa5c126c58067ae5c0e7643646d18cd6d96ce1f99c7b5873e
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.

1.322 × 10⁹⁴(95-digit number)
13223303795347584931…92324862406299291520
Discovered Prime Numbers
p_k = 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.

1
origin − 1
1.322 × 10⁹⁴(95-digit number)
13223303795347584931…92324862406299291519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.644 × 10⁹⁴(95-digit number)
26446607590695169862…84649724812598583039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.289 × 10⁹⁴(95-digit number)
52893215181390339725…69299449625197166079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.057 × 10⁹⁵(96-digit number)
10578643036278067945…38598899250394332159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.115 × 10⁹⁵(96-digit number)
21157286072556135890…77197798500788664319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.231 × 10⁹⁵(96-digit number)
42314572145112271780…54395597001577328639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.462 × 10⁹⁵(96-digit number)
84629144290224543561…08791194003154657279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.692 × 10⁹⁶(97-digit number)
16925828858044908712…17582388006309314559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.385 × 10⁹⁶(97-digit number)
33851657716089817424…35164776012618629119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.770 × 10⁹⁶(97-digit number)
67703315432179634848…70329552025237258239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
1.354 × 10⁹⁷(98-digit number)
13540663086435926969…40659104050474516479
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 consecutive prime numbers forming a Cunningham Chain of the First Kind. 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.

View full Prime Chain Discovery page →
★★★☆☆
Rarity
RareChain length 11
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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Verify on a Primecoin Node

Anyone running a Primecoin node can independently verify this block using the following RPC commands. Run these from the primecoin-cli command line or via the debug console in the Primecoin wallet.

1. Get block hash by height
getblockhash 857452

Returns the block hash for a given block height. Use this to confirm the hash shown above matches the chain.

2. Get full block data
getblock 195eacbcc89fc7d245a4c22c67974b4bbd5356d36614b66d4398e840470590fc

Returns the full block header including difficulty, prime chain origin, prime chain type, transaction IDs, and all other fields shown on this page.

How to run these commands: To verify this data independently, open a terminal on your own Primecoin node and run primecoin-cli <command>. Alternatively, open the Primecoin-Qt wallet, go to Help → Debug Window → Console, and type the command directly. The node must be fully synced to this block height for the commands to return results.

Cross-reference on Chainz Explorer

Chainz is an independent Primecoin block explorer. Compare this block's data to verify accuracy.

View Block #857,452 on Chainz ↗
Circulating Supply:57,984,282 XPM·at block #6,842,482 · updates every 60s
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