A092643 Number of consecutive prime runs of 3 primes congruent to 3 mod 4 below 10^n.

0, 0, 1, 36, 323, 2480, 20947, 183898, 1621279, 14492365, 131016136

Offset

1,4

Links

Table of n, a(n) for n=1..11.

Formula

Generate the prime sequence with primes labeled 1 mod 4 or 3 mod 4. Add count of primes to sequence if just 3 primes occur before interruption by a prime congruent to 1 mod 4.

Example

a(5)=323 because 323 sets of 3 primes occur below 10^5, each run interrupted by a prime congruent to 1 mod 4.

Crossrefs

Cf. A092642, A092644.

Sequence in context: A270601 A361187 A232828 * A045786 A237128 A171586

Adjacent sequences: A092640 A092641 A092642 * A092644 A092645 A092646

Keyword

more,nonn

Author

Enoch Haga, Mar 02 2004

Extensions

a(9)-a(11) from Chai Wah Wu, Mar 18 2018

Status

approved