A177357 Number of positive squares <= prime(n) - 3.

0, 1, 2, 2, 3, 3, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 7, 8, 8, 8, 8, 8, 9, 9, 9, 10, 10, 10, 10, 11, 11, 11, 11, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19, 19, 19, 19

Offset: 2

Author

Giovanni Teofilatto, May 07 2010

Keywords

• nonn

Crossrefs

Cf. A000006.

Programs

Maple

A000196 := proc(n) floor(sqrt(n)) ; end proc:
A086801 := proc(n) ithprime(n)-3 ; end proc:
A177357 := proc(n) A000196(A086801(n)) ; end proc: seq(A177357(n),n=2..90) ; # R. J. Mathar, May 09 2010

Mathematica

Floor[Sqrt[Prime[Range[2,80]]-3]] (* Harvey P. Dale, Dec 15 2018 *)

Formula

a(n) = A000196(A086801(n)). - R. J. Mathar, May 09 2010

Extensions

Edited by N. J. A. Sloane, May 08 2010

More terms from R. J. Mathar, May 09 2010

Reference redirected to a valid A-number by R. J. Mathar, May 09 2010