Search: id:A161912 Results 1-1 of 1 results found. %I A161912 %S A161912 0,0,0,0,1,1,1,1,1,4,2,6,4,4,4,6,7,7,7,9,5,7,7,11,11,12,10,10,6,8,14,16, 16,14,20,18,15,19,19,21,19,19,21,21,19,15,23,33,27,26,24,26,22,30, 28,30,28,26,28,30,20,28,38,36,31,31,37,41,45,43,39,43,39,43,45,43, 43,47,43,49,49,46,52,52,46,46,48,52,48,48,40,48,50,50,54,54,48,58, 54,66,63,71,69,73,67,65,71,75,69,69,67,69,63,63,67,73,69,67,69,71, 57 %N A161912 a(n) = A040976(n+1) - A006218(n). %p A161912 A006128 := proc(n) add(floor(n/k),k=1..n) ; end: A040976 := proc(n) ithprime(n)-2 ; end: %p A161912 A161912 := proc(n) A040976(n+1)-A006128(n) ;end: seq(A161912(n),n=0..120) ;# R. J. Mathar, Jul 01 2009 %Y A161912 Cf. A000005, A001223, A006218, A040976, A161911. %Y A161912 Sequence in context: A059853 A136527 A138614 this_sequence A162339 A021705 A135853 %Y A161912 Adjacent sequences: A161909 A161910 A161911 this_sequence A161913 A161914 A161915 %K A161912 easy,nonn %O A161912 0,10 %A A161912 Omar E. Pol (info(AT)polprimos), Jun 28 2009 %E A161912 Invalid formula deleted and sequence extended by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 01 2009 Search completed in 0.001 seconds