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A166722 a(n) is the number of divisors of A166721(n). 2
1, 3, 5, 9, 7, 15, 21, 27, 11, 25, 45, 13, 35, 33, 63, 75, 39, 81, 49, 17, 55, 105, 135, 99, 19, 65, 51, 189, 77, 125, 117, 147, 225, 165, 57, 243, 91, 175, 23, 85, 315, 195, 297, 153, 231, 95, 405, 245, 69, 375, 351, 119, 275, 441, 171, 121, 273, 567, 495, 255, 525 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

This is a permutation of the odd numbers A005408. - Alois P. Heinz, Mar 04 2018

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..300

EXAMPLE

a(8) = A000005(A166721(8)) = A000005(900) = A000005(2^2 * 3^2 * 5^2) = (2+1)*(2+1)*(2+1) = 27.

CROSSREFS

Cf. A000005, A005408, A048691, A136404, A152674, A166721.

Sequence in context: A250469 A003961 A100463 * A094549 A029642 A221967

Adjacent sequences:  A166719 A166720 A166721 * A166723 A166724 A166725

KEYWORD

easy,nonn

AUTHOR

Alexander Isaev (i2357(AT)mail.ru), Oct 20 2009

EXTENSIONS

Proper definition (and removal of obscure Comments entries) by Jon E. Schoenfield, Mar 03 2018

STATUS

approved

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Last modified December 8 02:30 EST 2019. Contains 329850 sequences. (Running on oeis4.)