The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A063402 a(0)=0; a(1)=1; a(2)=2; a(n)= a(n-1) + a(n-2)*a(n-3). 1
0, 1, 2, 2, 4, 8, 16, 48, 176, 944, 9392, 175536, 9041584, 1657675696, 1588781164720, 14989602831307184, 2633698912621747952304, 23815201278713350097371300784, 39478100701260806183512640492975852720 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
MATHEMATICA
nxt[{a_, b_, c_}]:={b, c, c+a*b}; NestList[nxt, {0, 1, 2}, 20][[All, 1]] (* Harvey P. Dale, Oct 16 2020 *)
PROG
(PARI) { for (n = 0, 29, if (n>2, a=a1 + a2*a3; a3=a2; a2=a1; a1=a, if (n==0, a=a3=0; a2=1; a1=2, if (n==1, a=1, a=2))); write("b063402.txt", n, " ", a) ) } \\ Harry J. Smith, Aug 20 2009
CROSSREFS
Cf. A006888.
Sequence in context: A123593 A122748 A108774 * A175195 A369289 A139800
KEYWORD
nonn,easy
AUTHOR
Olivier Gérard, Jul 16 2001
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 12 23:15 EDT 2024. Contains 373360 sequences. (Running on oeis4.)