A177785 a(n) = a(n-1)^2 - a(n-2) for n > 2; a(1)=3, a(2)=0.

3, 0, -3, 9, 84, 7047, 49660125, 2466128015008578, 6081787386410149117225363921959, 36988137813497592451208729538020214534589070415260614227389103

Offset

1,1

Comments

The Aho-Sloane paper describes how to analyze sequences of this type. - N. J. A. Sloane, Dec 02 2013

Links

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

A. V. Aho and N. J. A. Sloane, Some doubly exponential sequences, Fibonacci Quarterly, Vol. 11, No. 4 (1973), pp. 429-437, alternative link.

Formula

a(n) ~ c^(2^n), where c = 1.14848429555729513492678444046479599533741444456530988510700824973103959568... . - Vaclav Kotesovec, May 21 2015

Mathematica

RecurrenceTable[{a[1]==3, a[2]==0, a[n]==a[n-1]^2-a[n-2]}, a, {n, 10}] (* Harvey P. Dale, Jul 26 2014 *)

Crossrefs

Sequence in context: A104141 A279977 A060533 * A212036 A191619 A327245

Adjacent sequences: A177782 A177783 A177784 * A177786 A177787 A177788

Keyword

sign

Author

Liam Kirsh (liam.kirsh(AT)gmail.com), May 13 2010

Extensions

Sequence was provided without a definition; definition inferred and terms a(7)-a(10) added by Jon E. Schoenfield, Dec 02 2013

Status

approved