A126888 a(n) is the smallest positive integer such that floor(a(n)/d(a(n))) = n, or -1 if no such number exists, where d(m) is the number of positive divisors of m.

1, 5, 7, 28, 11, 13, 44, 17, 19, 63, 23, 51, 55, 29, 31, 49, 69, 37, 77, 41, 43, 91, 47, 147, 153, 53, 111, 115, 59, 61, 125, 129, 67, 207, 71, 73, 296, 155, 79, 121, 83, 680, 261, 89, 183, 185, 284, 97, 399, 101, 103, 209, 107, 109, 221, 113, 459, 235, 237, 363, 247, 249

Offset: 1

Author

Leroy Quet, Dec 30 2006

Keywords

• nonn

Links

• Hugo van der Sanden and D. W. Wilson, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000005, A126889, A078709, A125056, A125057.

Programs

Mathematica

f[n_] := Block[{k = 1},While[Floor[k/Length[Divisors[k]]] != n, k++ ];k];Table[f[n], {n, 62}] (* Ray Chandler, Jan 04 2007 *)

Extensions

Extended by Ray Chandler, Jan 04 2007.

Added escape clause to definition at the suggestion of Hugo van der Sanden. - N. J. A. Sloane, Jul 01 2022