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%I #15 Jul 25 2024 04:42:47
%S 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,
%T 16,16,14,20,18,15,19,19,21,19,19,21,21,19,15,23,33,27,26,24,26,22,30,
%U 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
%N a(n) = A040976(n+1) - A006218(n).
%p A006218 := proc(n) add(floor(n/k),k=1..n) ; end:
%p A040976 := proc(n) ithprime(n)-2 ; end:
%p A161912 := proc(n) A040976(n+1)-A006218(n) ;end:
%p seq(A161912(n),n=0..120) ; # _R. J. Mathar_, Jul 01 2009
%o (PARI) first(n)=my(v=primes(n+1),s); v[1]-=s=2; forfactored(k=1,n, v[k[1]+1]-=s+=numdiv(k)); v \\ _Charles R Greathouse IV_, Nov 03 2021
%Y Cf. A000005, A001223, A006218, A040976, A161911.
%K easy,nonn,less
%O 0,10
%A _Omar E. Pol_, Jun 28 2009
%E Invalid formula deleted and sequence extended by _R. J. Mathar_, Jul 01 2009