A092648 Number of consecutive prime runs of 5 primes congruent to 1 mod 4 below 10^n.

0, 0, 0, 3, 36, 344, 3491, 32628, 300541, 2771091, 25737994

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 5 primes occur before interruption by a prime congruent to 3 mod 4.

Example

a(6)=344 because 344 sets of 5 primes occur below 10^6, each run interrupted by a prime congruent to 3 mod 4.

Crossrefs

Cf. A092649, A092650.

Sequence in context: A003691 A038146 A067444 * A026121 A055303 A274403

Adjacent sequences: A092645 A092646 A092647 * A092649 A092650 A092651

Keyword

more,nonn

Author

Enoch Haga, Mar 02 2004

Extensions

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

Status

approved