A121644 Slowest increasing sequence with squarefree cumulative sums.

1, 2, 3, 4, 5, 6, 8, 9, 13, 14, 17, 19, 21, 23, 25, 27, 29, 31, 33, 36, 39, 41, 43, 44, 45, 48, 49, 50, 52, 53, 59, 61, 63, 64, 65, 67, 68, 69, 72, 73, 75, 77, 82, 84, 86, 87, 88, 89, 91, 92, 93, 94, 96, 98, 99, 100, 101, 102, 104, 106, 108, 110, 116, 117, 119, 120, 121, 123

Offset: 1

Author

Zak Seidov, Aug 13 2006

Keywords

• nonn

Links

• Zak Seidov, Table of n, a(n) for n = 1..1000.

Crossrefs

Cf. A084693 (non-monotonic version).

Programs

Mathematica

a = {1}; Do[k = 1; While[Nand[k > a[[n]], SquareFreeQ[Sum[a[[i]], {i, n}] + k]], k++]; AppendTo[a, k], {n, 67}]; a (* Michael De Vlieger, Sep 03 2015 *)