A140127 The first five terms are 1, after that, a(n)=a(n-1)^2-a(n-2)-a(n-3)-a(n-4)-a(n-5).

1, 1, 1, 1, 1, -3, 5, 25, 621, 385613, 148697385121, 22110912341822991798377, 488892444587780299304228901641309659922062749, 239015822375015830469277614767879892635108603674971498096787773471947363213442923403867269

Offset

1,6

Links

Table of n, a(n) for n=1..14.

Example

a(7)=5 because (-3)^2-1-1-1-1=5.

Maple

a:= proc(n) option remember;
  `if`(n<6, 1, a(n-1)^2 -a(n-2) -a(n-3) -a(n-4) -a(n-5))
end:
seq(a(n), n=1..14); # Alois P. Heinz, Jan 17 2011

Mathematica

F[x_] := F[x - 1]^2 - F[x - 2] - F[x - 3] - F[x - 4] - F[x - 5]; F[1] = F[2] = F[3] = F[4] = F[5] = 1
RecurrenceTable[{a[1]==a[2]==a[3]==a[4]==a[5]==1, a[n]==a[n-1]^2-a[n-2]-a[n-3]-a[n-4]-a[n-5]}, a, {n, 15}] (* Harvey P. Dale, Aug 01 2021 *)

Crossrefs

Sequence in context: A074701 A318179 A327468 * A226318 A154143 A101611

Adjacent sequences: A140124 A140125 A140126 * A140128 A140129 A140130

Keyword

sign

Author

Ben Branman, Jun 21 2008

Extensions

More terms from Alois P. Heinz, Jan 17 2011

Status

approved