A051261 Main diagonal of A018219, i.e., (n, n, a_n) is a winning position.

0, 4, 6, 1, 3, 7, 11, 2, 5, 10, 17, 23, 21, 9, 28, 26, 24, 8, 34, 12, 35, 13, 32, 29, 44, 19, 45, 15, 18, 14, 57, 56, 16, 20, 58, 48, 25, 54, 73, 76, 72, 27, 75, 82, 62, 66, 84, 87, 71, 78, 95, 31, 74, 94, 97, 103, 22, 40, 39, 30, 86, 33, 41, 91, 46, 42, 117, 119, 122, 37

Offset

0,2

Links

Table of n, a(n) for n=0..69.

Index entries for sequences that are permutations of the natural numbers

Mathematica

mex[s_] := Min[Complement[Range[0, Max[{s, -1}] + 1], Flatten[s]]];
f[s_] := Join[s, s + Table[i, {i, Length[s]}]];
T[n_, k_] := T[n, k] = mex[{f[Table[T[n - i, k], {i, n}]], f[Table[T[n, k - i], {i, k}]], f[Table[T[n - i, k - i], {i, Min[n, k]}]]}];
a[n_] := T[n, n];
Table[a[n], {n, 0, 69}] (* Jean-François Alcover, Aug 19 2019, from A018219 Mma code *)

Crossrefs

Cf. A018219, Inverse is A077226.

Sequence in context: A246489 A343624 A309445 * A247621 A245275 A030169

Adjacent sequences: A051258 A051259 A051260 * A051262 A051263 A051264

Keyword

nonn,nice

Author

Michael Kleber

Extensions

Edited and extended by Christian G. Bower, Oct 29 2002

Status

approved