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A328334
Forward difference of difference between 2^n and the next smaller power of 3.
1
1, 0, 4, 2, -2, 32, 10, -34, 256, 26, 1024, 590, -278, 8192, 3262, -6598, 65536, 12974, 262144, 169994, -14306, 2097152, 1005658, -1177330, 16777216, 4856618, -18984578, 134217728, 10155130, 536870912, 298900846, -177039286, 4294967296, 1616365790, -3740837222
OFFSET
0,3
COMMENTS
a(n) is even for n >= 1.
LINKS
FORMULA
a(n) = A063005(n+1) - A063005(n).
MAPLE
b:= proc(n) option remember; (t-> t-3^ilog[3](t))(2^n) end:
a:= n-> b(n+1)-b(n):
seq(a(n), n=0..40);
CROSSREFS
Cf. A063005.
Sequence in context: A350149 A350609 A261253 * A359060 A134977 A199081
KEYWORD
sign
AUTHOR
Alois P. Heinz, Oct 12 2019
STATUS
approved