1,3

Robert Israel, Table of n, a(n) for n = 1..10000

Altug Alkan, Plot for n=0..10^6

a:= proc(n) option remember;

procname(procname(n-1)-1) + procname(n-procname(n-3)-1)

end proc:

a(1):= 1: a(2):= 1: a(3):= 2:

map(a, [$1..100]);

a[1] = a[2] = 1; a[3] = 2; a[n_] := a[n] = a[a[n - 1] - 1] + a[n - a[n - 3] - 1]; Array[a, 81] (* Michael De Vlieger, Mar 28 2017 *)

Cf. A004001, A005185, A055748.

Sequence in context: A194343 A071860 A004788 * A034584 A035430 A167227

Adjacent sequences: A284520 A284521 A284522 * A284524 A284525 A284526

nonn,look

Altug Alkan and Robert Israel, Mar 28 2017

approved