A076655 - OEIS

A076655

Numerator of a(n), where for n > 2, a(n)=-1/a(n-1)+1/a(n-2), a(1)=1, a(2)=2.

1, 2, 1, -3, 8, -25, 267, -11408, 4063825, -61874069763, 376863853335803168, -33029401504744904404673707225

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OFFSET

1,2

LINKS

FORMULA

a(n>2)=-1/a(n-1)+1/a(n-2), a(1)=1, a(2)=2, a(n)->-(-1)^n sqrt(2).

EXAMPLE

a(3)=-1/a(2)+1/a(1)=-1/2+1=1/2, therefore in the sequence, 3rd term is 1.

CROSSREFS

KEYWORD

sign,frac

AUTHOR

Zak Seidov, Oct 24 2002

STATUS

approved