A013930 Sum of first a(n) squarefrees is squarefree.

1, 2, 3, 4, 5, 7, 9, 11, 13, 15, 17, 19, 20, 23, 25, 26, 27, 29, 32, 34, 37, 40, 41, 42, 43, 44, 46, 47, 49, 50, 51, 53, 54, 56, 58, 60, 61, 63, 64, 65, 69, 70, 71, 74, 76, 77, 79, 80, 81, 82, 83, 84, 86, 88, 89, 90, 92, 94, 95, 96, 98, 100, 102, 103, 104, 106, 107, 108, 110, 111

Offset

1,2

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Mathematica

Position[Accumulate[Select[Range[200], SquareFreeQ]], _?SquareFreeQ, Heads -> False] // Flatten (* Amiram Eldar, Mar 07 2021 *)

Crossrefs

Cf. A005117, A013931, A013932.

Sequence in context: A339968 A316268 A026285 * A004281 A004276 A033057

Adjacent sequences: A013927 A013928 A013929 * A013931 A013932 A013933

Keyword

nonn

Author

Henri Lifchitz

Extensions

More terms from David W. Wilson

Status

approved