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A249717
The smallest prime whose square divides the first nonsquarefree number on row n of Pascal's triangle, 1 if all terms on that row are squarefree.
6
1, 1, 1, 1, 2, 1, 2, 1, 2, 3, 3, 1, 2, 3, 2, 3, 2, 2, 3, 3, 2, 3, 2, 1, 2, 5, 5, 3, 2, 3, 2, 3, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 2, 3, 2, 3, 3, 3, 2, 7, 5, 5, 2, 5, 3, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 5, 2, 5, 2, 3, 2, 3, 3, 3, 2, 3, 2, 3, 2, 2, 3, 3, 2, 3, 2, 3, 2, 2, 7, 3, 2, 5, 2, 5, 2, 2, 2, 5, 2, 3, 2, 3, 2, 2, 2, 2, 2, 3, 3, 3, 2
OFFSET
0,5
COMMENTS
All such n, for which a(n) < 3, form a subsequence of A249724.
FORMULA
a(n) = A249739(A249716(n)).
PROG
(Scheme) (define (A249717 n) (A249739 (A249716 n)))
CROSSREFS
Differs from A249718 for the first time at n=36, where a(36) = 2, while A249718(36) = 3.
Sequence in context: A257806 A035391 A242552 * A249718 A244518 A367251
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 04 2014
STATUS
approved