A376156 a(n) is the least number that is the sum of the nonprime divisors of k for exactly n different k.
2, 5, 23, 83, 536, 2519, 45359, 16736, 743398, 1908958, 3386606, 9295535
Offset: 0
Examples
2 is not the sum of the nonprime divisors of any k. 5 is the sum of the nonprime divisors of 4 (1 + 4 = 5). 23 is the sum of the nonprime divisors of 12 (1 + 4 + 6 + 12) and of 22 (1 + 22). 83 is the sum of the nonprime divisors of 40 (1 + 4 + 8 + 10 + 20 + 40) and 52 (1 + 4 + 26 + 52) and 82 (1 + 82).
Crossrefs
Cf. A023890.
Programs
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Maple
N:= 10^6: # for terms < 10^6 f:= proc(n) convert(remove(isprime, numtheory:-divisors(n)),`+`) end proc: R:= Vector(N): for i from 1 to N do v:= f(i); if v <= N then R[v]:= R[v]+1 fi od: m:= convert(R,set)[-2]: V:= Array(0..m): count:= 0: for i from 2 while count < m+1 do if V[R[i]] = 0 then V[R[i]]:= i; count:= count+1 fi od: convert(V,list);