A092657 Number of consecutive prime runs of 8 primes congruent to 1 mod 4 below 10^n.

0, 0, 0, 0, 0, 16, 221, 2213, 21794, 214836, 2089934

Offset

1,6

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

Example

a(6)=16 because 16 sets of 8 primes occur below 10^6, each run interrupted by a prime congruent to 3 mod 4.

Crossrefs

Cf. A092658 A092659.

Sequence in context: A130606 A193380 A076073 * A078266 A093746 A118779

Adjacent sequences: A092654 A092655 A092656 * A092658 A092659 A092660

Keyword

more,nonn

Author

Enoch Haga, Mar 02 2004

Extensions

a(9) and a(10) from Sean A. Irvine, Oct 20 2011

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

Status

approved