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A061999 a(n)=2a(n-1)^2-2a(n-2)^2. 2
0, 1, 2, 6, 64, 8120, 131860608, 34774439752390528, 2418523320185277177863741363978240, 11698510100560033501377640350194228137500049288930688305497138757632 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(3)=2*2^2-2*1^2=6

LINKS

Harry J. Smith, Table of n, a(n) for n=0,...,12

FORMULA

a(n)=A062000(n)/2

MATHEMATICA

Join[{a=0, b=1}, Table[c=2*b^2-2*a^2; a=b; b=c, {n, 10}]] (* Vladimir Joseph Stephan Orlovsky, Jan 22 2011*)

PROG

(PARI) { for (n=0, 12, if (n>1, a=2*a1^2-2*a2^2; a2=a1; a1=a, if (n==0, a=a2=0, a=a1=1)); write("b061999.txt", n, " ", a) ) } \\ Harry J. Smith, Jul 29 2009

CROSSREFS

Sequence in context: A241590 A052522 A193609 * A066756 A070872 A055685

Adjacent sequences:  A061996 A061997 A061998 * A062000 A062001 A062002

KEYWORD

nonn

AUTHOR

Henry Bottomley, May 29 2001

STATUS

approved

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Last modified April 25 12:04 EDT 2019. Contains 322456 sequences. (Running on oeis4.)