A280692 a(n) = A003961(n) - A250469(n).

0, 0, 0, 0, 0, 0, 0, 6, 0, -6, 0, 12, 0, -6, 0, 36, 0, 24, 0, 6, 0, -24, 0, 66, 0, -24, 60, 18, 0, 18, 0, 150, -20, -42, 0, 120, 0, -42, -10, 72, 0, 42, 0, -12, 60, -48, 0, 264, 0, 0, -30, 0, 0, 216, 0, 132, -30, -78, 0, 138, 0, -72, 120, 540, 0, 0, 0, -30, -30, 24, 0, 462, 0, -96, 60, -18, 0, 24, 0, 330, 420, -114, 0, 246

Offset: 1

Author

Antti Karttunen, Mar 08 2017

Keywords

• sign

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10067

Crossrefs

Cf. A003961, A250469, A249820, A280492, A280497, A280498, A280702.

Cf. A280693 (gives the positions of zeros).

Cf. also arrays A083221 and A246278.

Programs

Mathematica

f[n_] := f[n] = Which[n == 1, 1, PrimeQ@ n, NextPrime@ n, True, Times @@ Replace[FactorInteger[n], {p_, e_} :> f[p]^e, 1]]; g[n_] := If[n == 1, 0, PrimePi@ FactorInteger[n][[1, 1]]]; Function[s, MapIndexed[ Function[{m, n}, f@ n - Lookup[s, g[n] + 1][[m]] + Boole[n == 1]][#1, First@ #2] &, #] &@ Map[Position[Lookup[s, g@ #], #][[1, 1]] &, Range@ 120]]@ PositionIndex@ Array[g, 10^4] (* Michael De Vlieger, Mar 09 2017, Version 10 *)

Scheme

(define (A280692 n) (- (A003961 n) (A250469 n)))

Formula

a(n) = A003961(n) - A250469(n).