A178503 n minus totally additive with a(p)=PrimePi(p), where PrimePi(n)=A000720(n).

1, 1, 1, 2, 2, 3, 3, 5, 5, 6, 6, 8, 7, 9, 10, 12, 10, 13, 11, 15, 15, 16, 14, 19, 19, 19, 21, 22, 19, 24, 20, 27, 26, 26, 28, 30, 25, 29, 31, 34, 28, 35, 29, 37, 38, 36, 32, 42, 41, 43, 42, 44, 37, 47, 47, 49, 47, 47, 42, 53, 43, 50, 55, 58, 56, 58, 48, 59, 58, 62, 51, 65, 52, 61

Offset: 1

Author

Juri-Stepan Gerasimov, Apr 19 2010

Keywords

• nonn

Crossrefs

Cf. A000027, A000720, A056239.

Programs

Maple

From R. J. Mathar, Apr 20 2010: (Start)
A056239 := proc(n) add( numtheory[pi](op(1,p))*op(2,p), p = ifactors(n)[2]) ; end proc:
A178503 := proc(n) n-A056239(n) ; end proc: seq(A178503(n),n=1..80) ; (End)

Formula

a(n) = A000027(n) - A056239(n).

Extensions

Corrected (a 27 replaced with 28) by R. J. Mathar, Apr 20 2010