A227386 a(n) = n - 1 - a(a(n-1)) - a(a(a(n-2))) - a(a(a(a(n-3)))) - a(a(a(a(a(n-4))))) - ... with a(0) = 0.

0, 0, 1, 2, 2, 3, 3, 3, 4, 5, 5, 5, 5, 6, 7, 8, 8, 9, 9, 9, 9, 9, 10, 11, 12, 13, 13, 14, 14, 15, 15, 15, 16, 17, 17, 17, 17, 17, 17, 18, 19, 20, 21, 22, 22, 23, 23, 24, 24, 25, 25, 25, 26, 27, 27, 27, 28, 29, 29, 29, 29, 30, 31, 32, 32, 33, 33, 33, 33, 33

Offset

0,4

Links

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

Mathematica

a[n_] := a[n] = Which[n ==0, 0, True, n - 1 - Sum[Nest[a, n - i, i + 1], {i, 1, n}]]; Table[a[n], {n, 0, 100}]

Crossrefs

Cf. A227145.

Sequence in context: A153112 A005350 A055037 * A351833 A354967 A125186

Adjacent sequences: A227383 A227384 A227385 * A227387 A227388 A227389

Keyword

nonn

Author

José María Grau Ribas, Jul 09 2013

Status

approved