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A087129
First differences of A087128.
2
1, 3, 1, 7, 9, 3, 9, 3, 9, 12, 3, 12, 24, 9, 36, 3, 33, 3, 12, 9, 3, 12, 9, 12, 15, 24, 9, 12, 15, 33, 12, 24, 3, 9, 36, 3, 9, 24, 36, 27, 12, 12, 9, 3, 21, 96, 3, 9, 3, 12, 9, 3, 12, 105, 3, 60, 12, 9, 39, 45, 27, 9, 12, 3, 12, 12, 45, 12, 15, 33, 15, 21, 3, 9, 3, 12, 9, 24, 3, 33, 15, 9
OFFSET
1,2
COMMENTS
It appears that, for n>4, a(n)=3k, for some integer k where k is not equal to 2 (mod 4). This has been verified for more than 3500 terms.
CROSSREFS
Cf. A087128.
Sequence in context: A329943 A372908 A011207 * A286436 A011308 A347840
KEYWORD
nonn
AUTHOR
John W. Layman, Aug 16 2003
STATUS
approved