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Home/Chain Registry/Block #149,944

Block #149,944

1CCLength 9β˜…β˜†β˜†β˜†β˜†

Cunningham Chain of the First Kind Β· Discovered 9/4/2013, 5:06:53 PM Β· Difficulty 9.8581 Β· 6,666,929 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a1c7f37e26aa3b669aebfe7344a992f8e5964ffecbf9c3cc077fb4665c779e1e
View on Chainz β†—

Height

#149,944

Difficulty

9.858052

Transactions

1

Size

199 B

Version

2

Bits

09dba948

Nonce

367,212

Timestamp

9/4/2013, 5:06:53 PM

Confirmations

6,666,929

Merkle Root

2a39f83262caff2ef50fd197360ed4eec7fa00c594f3f7dcca36370cc6b42f3c
Transactions (1)
Coinbase2a39f83262caff…36370cc6b42f3c
1 in β†’ 1 out10.2700 XPM109 B
AMjazV56…tVUuP32T
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) β€” it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

6.012 Γ— 10⁹⁴(95-digit number)
60122120425840217474…51078580619086111360
Discovered Prime Numbers
p_k = 2^k Γ— origin βˆ’ 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 βˆ’ 1
6.012 Γ— 10⁹⁴(95-digit number)
60122120425840217474…51078580619086111359
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
2
2^1 Γ— origin βˆ’ 1
1.202 Γ— 10⁹⁡(96-digit number)
12024424085168043494…02157161238172222719
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
3
2^2 Γ— origin βˆ’ 1
2.404 Γ— 10⁹⁡(96-digit number)
24048848170336086989…04314322476344445439
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
4
2^3 Γ— origin βˆ’ 1
4.809 Γ— 10⁹⁡(96-digit number)
48097696340672173979…08628644952688890879
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
5
2^4 Γ— origin βˆ’ 1
9.619 Γ— 10⁹⁡(96-digit number)
96195392681344347959…17257289905377781759
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
6
2^5 Γ— origin βˆ’ 1
1.923 Γ— 10⁹⁢(97-digit number)
19239078536268869591…34514579810755563519
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
7
2^6 Γ— origin βˆ’ 1
3.847 Γ— 10⁹⁢(97-digit number)
38478157072537739183…69029159621511127039
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
8
2^7 Γ— origin βˆ’ 1
7.695 Γ— 10⁹⁢(97-digit number)
76956314145075478367…38058319243022254079
Verify on FactorDB β†—Wolfram Alpha β†—
Γ—2+1 β†’
9
2^8 Γ— origin βˆ’ 1
1.539 Γ— 10⁹⁷(98-digit number)
15391262829015095673…76116638486044508159
Verify on FactorDB β†—Wolfram Alpha β†—

What this block proved

The miner who found this block proved the existence of 9 consecutive prime numbers forming a Cunningham Chain of the First Kind. The prime chain origin β€” the large number shown above β€” 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 β†’
β˜…β˜†β˜†β˜†β˜†
Rarity
CommonChain length 9
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 Γ— 3 Γ— 5 Γ— 7 Γ— …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial β€” that divisibility is part of the proof.

Prime Chain Origin = First Prime Γ— Primorial (2Β·3Β·5Β·7Β·11·…)
Source: Primecoin prime.cpp β€” CheckPrimeProofOfWork()

This is why the origin has many small prime factors β€” those factors are the primorial divisor. The chain then extends from the first prime using the 1CC formula:

1CC: p₁ (first prime), pβ‚‚ = 2p₁ + 1, p₃ = 2pβ‚‚ + 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 149944

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 a1c7f37e26aa3b669aebfe7344a992f8e5964ffecbf9c3cc077fb4665c779e1e

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 β†’ Debug Window β†’ 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 #149,944 on Chainz β†—
Circulating Supply:57,779,022 XPMΒ·at block #6,816,872 Β· updates every 60s
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