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A099175
a(1) = 1, a(2) = 8; for n > 2: a(n) = a(n-1)*(3*a(n-1)-2).
1
1, 8, 176, 92576, 25710762176, 1983129874961075240576, 11798412302889389755255045998938726679954176, 417607598606915139792416465578985202696175989567316713156694229302007260054247019608576
OFFSET
1,2
COMMENTS
n*(3n-2) is the n-th octagonal number (A000567).
FORMULA
a(n) = (A003487(n-1)+1)/3 for n >= 2. - Ondrej Kutal, Sep 08 2023
MATHEMATICA
Join[{1}, NestList[ #*(3*# - 2) &, 8, 7]]
CROSSREFS
Sequence in context: A221631 A064342 A251578 * A000839 A001596 A221115
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Nov 15 2004
EXTENSIONS
Edited by Stefan Steinerberger, Jul 25 2007
STATUS
approved