A141126 - OEIS

A141126

a(n+1) = a(n)-n^2 if positive and new, else a(n+1) = a(n)+n^2; a(0)=1.

1, 1, 2, 6, 15, 31, 56, 20, 69, 5, 86, 186, 65, 209, 40, 236, 11, 267, 556, 232, 593, 193, 634, 150, 679, 103, 728, 52, 781, 1565, 724, 1624, 663, 1687, 598, 1754, 529, 1825, 456, 1900, 379, 1979, 298, 2062, 213, 2149, 124, 2240, 4449, 2145, 4546, 2046, 4647

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OFFSET

0,3

LINKS

Indranil Ghosh, Table of n, a(n) for n = 0..50000 (terms 0..240 from Reinhard Zumkeller)

Index entries for sequences related to Recamán's sequence.

MATHEMATICA

s={1}; Do[nx=s[[-1]]-n^2; If[nx>0&&!MemberQ[s, nx], AppendTo[s, nx], AppendTo[s, nx+2n^2]], {n, 0, 51}]; s (* James C. McMahon, Jul 17 2025 *)

CROSSREFS

Cf. A063733.

Sequence in context: A355057 A236111 A230455 * A056520 A289961 A290068

Adjacent sequences: A141123 A141124 A141125 * A141127 A141128 A141129

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 05 2008

STATUS

approved