A000284 a(n) = a(n-1)^3 + a(n-2) with a(0)=0, a(1)=1.

0, 1, 1, 2, 9, 731, 390617900, 59601394712394173339000731, 211723599072542785377729319366442939995427829921816290889198752331804918235791

Offset: 0

Author

Stephen J. Greenfield (greenfie(AT)math.rutgers.edu)

Keywords

• nonn
• easy

Links

• John Cerkan, Table of n, a(n) for n = 0..10

Crossrefs

Cf. A058182.

Programs

Maple

A000284 := proc(n) option remember; if n <= 1 then n else A000284(n-2)+A000284(n-1)^3; fi; end;
a[-2]:=0: a[-1]:=1: a[0]:=1: a[1]:=2: for n from 2 to 6 do a[n]:=a[n-1]^3+a[n-2] od: seq(a[n], n=-2..6); # Zerinvary Lajos, Mar 19 2009

Mathematica

RecurrenceTable[{a[n] == a[n-1]^3 + a[n-2], a[0] == 0, a[1] == 1}, a, {n, 0, 8}] (* Jean-François Alcover, Feb 06 2016 *)
nxt[{a_,b_}]:={b,b^3+a}; NestList[nxt,{0,1},9][[All,1]] (* Harvey P. Dale, May 08 2020 *)

Formula

For n>0, a(n) = floor(c^(3^n)) where c=1.0275090796393628012075291021962112731026759143420911102331653107087209649910... - Gerald McGarvey, Nov 28 2007

Extensions

a(9) from Vincenzo Librandi, Apr 26 2010