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.

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.

Links

Table of n, a(n) for n=0..120.

Formula

a(n) = A249739(A249716(n)).

Prog

(Scheme) (define (A249717 n) (A249739 (A249716 n)))

Crossrefs

Cf. A249716, A249739, A249724.

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

Adjacent sequences: A249714 A249715 A249716 * A249718 A249719 A249720

Keyword

nonn

Author

Antti Karttunen, Nov 04 2014

Status

approved