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A145647
First differences of A145646.
2
2734, 4556, 6379, 8202, 10024, 11846, 13669, 15492, 17314, 19136, 20959, 22782, 24604
OFFSET
1,1
COMMENTS
Essentially (rounding effects ignored) 2*n+1 divided by the scaled constant A081821.
FORMULA
Conjectures from Colin Barker, May 08 2019: (Start)
G.f.: x*(2734 - 912*x + 2735*x^2 - 912*x^3) / ((1 - x)^2*(1 + x^2)).
a(n) = (3646 + (-i)^n + i^n + 7290*n) / 4 where i = sqrt(-1).
a(n) = 2*a(n-1) - 2*a(n-2) + 2*a(n-3) - a(n-4) for n>4.
(End)
CROSSREFS
Sequence in context: A076575 A015423 A260543 * A251946 A045155 A251989
KEYWORD
nonn,easy,less
AUTHOR
Paul Curtz, Oct 15 2008
EXTENSIONS
Edited by N. J. A. Sloane, Oct 15 2008 and R. J. Mathar, Oct 17 2008
Deleted keyword more: we do not want more terms of this ill-defined sequence. - R. J. Mathar, May 12 2019
STATUS
approved