

A132418


Sequence is identical to its third differences in absolute values: a(n+k)=3a(n+k1)3a(n+k2)+2a(n+k3), k=0, 1, 2, 3, 4, a(n+5)=3a(n+4)3a(n+3), n > 2.


1



1, 2, 3, 5, 10, 21, 43, 86, 129, 215, 430, 903, 1849, 3698, 5547, 9245, 18490, 38829, 79507
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OFFSET

0,2


COMMENTS

(6n+1)th terms: 43, 43^2, 43^3, 43^4?


LINKS

Table of n, a(n) for n=0..18.
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 43).


FORMULA

6nth terms of a(n) opposite to the 6th of third differences. These terms are 21=3*7, 903=21*43, 38829=21*43^2.


MATHEMATICA

LinearRecurrence[{0, 0, 0, 0, 0, 43}, {1, 2, 3, 5, 10, 21}, 19] (* Ray Chandler, Sep 23 2015 *)


CROSSREFS

Sequence in context: A125312 A300550 A014626 * A024494 A131708 A002991
Adjacent sequences: A132415 A132416 A132417 * A132419 A132420 A132421


KEYWORD

nonn


AUTHOR

Paul Curtz, Nov 13 2007


STATUS

approved



