A091099 Number of primes of the form 4k+3 less than 10^n.

2, 13, 87, 619, 4808, 39322, 332398, 2880950, 25424042, 227529235, 2059034532, 18803987677, 173032827655, 1602470967129, 14922285687184, 139619172246129, 1311778581969146, 12369977145161275, 117028833678543917, 1110409801410336132

Offset

1,1

Links

Table of n, a(n) for n=1..20.

Marc Deleglise, Pierre Dusart, and Xavier-Francois Roblot, Counting primes in residue classes, Math. Comp. 73 (2004), no. 247, 1565-1575

Daniel Pareja, Prime Number Races

Eric Weisstein's World of Mathematics, Modular Prime Counting Function

Mathematica

cnt=0; k=0; Table[lim=10^n; While[4k+3<lim, If[ PrimeQ[4k+3], cnt++ ]; k++ ]; cnt, {n, 6}]

Crossrefs

Cf. A091098 (number of primes of the form 4k+1 less than 10^n).

Sequence in context: A162275 A092070 A091116 * A092849 A300429 A106938

Adjacent sequences: A091096 A091097 A091098 * A091100 A091101 A091102

Keyword

nonn

Author

T. D. Noe, Dec 19 2003

Extensions

a(10)-a(16) from Robert G. Wilson v, Dec 22 2003

a(17)-a(20) from Marc Deleglise, Jun 28 2007

Status

approved