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A188313 A (25,-29) Somos-4 sequence. 2
1, 3, 23, 314, 8209, 620297, 126742987, 47301104551, 32606721084786, 61958046554226593, 334806306946199122193, 3416372868727801226636179, 62595441409640805744780870839, 2993270782370572835241882188306602, 424202695773047673359251734568172738737 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Hankel transform of A188312.

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..74

FORMULA

a(n) = (25*a(n-1)*a(n-3) - 29*a(n-2)^2)/a(n-4), n>=4.

MATHEMATICA

Join[{1, 3, 23, 314}, RecurrenceTable[{a[n] == (25*a[n - 1]*a[n - 3] - 29*a[n - 2]^2)/a[n - 4], a[4] == 8209, a[5] == 620297, a[6] == 126742987, a[7] == 47301104551}, a, {n, 4, 25}]]  (* G. C. Greubel, Aug 14 2018 *)

PROG

(MAGMA) I:=[8209, 620297, 126742987, 47301104551]; [1, 3, 23, 314] cat [n le 4 select I[n] else (25*Self(n-1)*Self(n-3) - 29*Self(n-2)^2)/Self(n-4): n in [1..30]]; // G. C. Greubel, Aug 14 2018

CROSSREFS

Sequence in context: A307418 A231788 A088692 * A227821 A222076 A129458

Adjacent sequences:  A188310 A188311 A188312 * A188314 A188315 A188316

KEYWORD

nonn,easy

AUTHOR

Paul Barry, Mar 28 2011

STATUS

approved

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Last modified February 17 02:22 EST 2020. Contains 331976 sequences. (Running on oeis4.)