A213637 Values of n for which A213636(n) = 1.

1, 3, 4, 5, 7, 9, 10, 11, 13, 15, 16, 17, 19, 21, 22, 23, 25, 27, 28, 29, 31, 33, 34, 35, 36, 37, 39, 40, 41, 43, 45, 46, 47, 49, 51, 52, 53, 55, 57, 58, 59, 61, 63, 64, 65, 67, 69, 70, 71, 73, 75, 76, 77, 79, 81, 82, 83, 85, 87, 88, 89, 91, 93, 94, 95, 96, 97, 99

Offset: 1

Author

Clark Kimberling, Jun 16 2012

Keywords

• nonn
• easy

Comments

a(n) is the position of the n-th 1 in the sequence of remainders when each positive integer is divided by its least nondivisor (as in A007978).

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Programs

Mathematica

(See A213636.)
rem[n_]:=Module[{lnd=First[Complement[Range[n],Divisors[n]]]},Mod[n,lnd]];Flatten[Position[Join[{1,2},Array[rem,100,3]],1]] (* Harvey P. Dale, Feb 07 2014 *)