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A277715
Row 5 of A277710: Positions of 5's in A264977; positions of 10's in A277330.
6
9, 21, 45, 93, 189, 381, 657, 765, 873, 1317, 1533, 1749, 2457, 2637, 3069, 3501, 4329, 4917, 5241, 5277, 5745, 6141, 6345, 7005, 8661, 9561, 9837, 10017, 10485, 10557, 11493, 12285, 12693, 14013, 15129, 17325, 17985, 19125, 19677, 20037, 20973, 21117, 21969, 22989, 24573, 25389, 26793, 28029, 30261, 31545, 34653, 35973
OFFSET
1,1
COMMENTS
Positions in A260443 of terms that are ten times a perfect square (terms in A033583, although not all of them are present in A260443).
It seems that A068156 from 9 onward is a subsequence, which (if true) would also be a sufficient condition for this sequence to be infinite.
LINKS
FORMULA
A277716(n) = a(n)/3.
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A277715 (MATCHING-POS 1 1 (lambda (n) (= 5 (A264977 n)))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 29 2016
STATUS
approved