A109173 Recursive form of A109845 but with a(1)=1.

1, 3, 5, 31, 929, 863971, 746445024869, 557180175152428473492031, 310449747582890872093779269721785644810947012929, 96379045774280656880008037888192772255684941220159788508646084243678677683026025975278640171971

Offset

1,2

Comments

The next term -- a(11) -- has 190 digits. - Harvey P. Dale, Aug 29 2012

Links

Table of n, a(n) for n=1..10.

Formula

a(1) = 1, a(n)=a(n-1)^2+(-1)^n*a(n-1)+(-1)^n

Maple

a := proc(n) option remember; if n=1 then 1 else a(n-1)^2+(-1)^n*a(n-1)+(-1)^n fi end:

Mathematica

RecurrenceTable[{a[1]==1, a[n]==a[n-1]^2+(-1)^n a[n-1]+(-1)^n}, a, {n, 10}] (* Harvey P. Dale, Aug 29 2012 *)

Crossrefs

Cf. A109845.

Sequence in context: A309725 A290888 A318554 * A179387 A295364 A199774

Adjacent sequences: A109170 A109171 A109172 * A109174 A109175 A109176

Keyword

nonn

Author

Walter Kehowski, Aug 18 2005

Extensions

More terms from Harvey P. Dale, Aug 29 2012

Status

approved