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A157101 A Somos-4 variant. 1
1, -1, -5, -4, 29, 129, -65, -3689, -16264, 113689, 2382785, 7001471, -398035821, -7911171596, 43244638645, 6480598259201, 124106986093951, -5987117709349201, -541051130050800400, -4830209396684261199 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Hankel transform of A157100.

LINKS

Table of n, a(n) for n=0..19.

FORMULA

a(0)=1,a(1)=-1,a(2)=-5,a(3)=-4, for n >= 4, a(n)=(a(n-1)a(n-3)+a(n-2)^2)/a(n-4).

a(n) = A051138(n+1) for all n in Z. - Michael Somos, Jul 17 2016

CROSSREFS

Cf. A051138.

Sequence in context: A024067 A192778 A051138 * A237648 A091001 A297936

Adjacent sequences:  A157098 A157099 A157100 * A157102 A157103 A157104

KEYWORD

easy,sign

AUTHOR

Paul Barry, Feb 22 2009

STATUS

approved

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Last modified December 13 08:08 EST 2018. Contains 318082 sequences. (Running on oeis4.)