

A135372


Highly composite numbers + 1.


0



2, 3, 5, 7, 13, 25, 37, 49, 61, 121, 181, 241, 361, 721, 841, 1261, 1681, 2521, 5041, 7561, 10081, 15121, 20161, 25201, 27721, 45361, 50401, 55441, 83161, 110881, 166321, 221761, 277201, 332641, 498961, 554401, 665281, 720721, 1081081
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OFFSET

1,1


COMMENTS

a(n) prime for n = 1, 2, 3, 4, 5, 7, 9, 11, 12, 18, 20, 22, 23, 26, 28, 30, 34, 35, ... a(n) square of prime for n = 6, 8, 10, 13, 15, 17, 19, ... a(n) is not a prime power for n = 14 (semiprime), 16 (semiprime), 21 (semiprime), 24 (3almost prime), 25 (semiprime), 27 (semiprime), 29 (semiprime), 31 (semiprime), 32 (semiprime), 33 (semiprime), 36 (semiprime), 37 (semiprime), 38 (semiprime), 39 (3almost prime), 40 (semiprime), 41 (semiprime).


LINKS

Table of n, a(n) for n=1..39.


FORMULA

a(n) = A002182(n)+1.


CROSSREFS

Cf. A000040, A001248, A002182.
Sequence in context: A124147 A227627 A335116 * A037021 A114741 A096177
Adjacent sequences: A135369 A135370 A135371 * A135373 A135374 A135375


KEYWORD

easy,nonn


AUTHOR

Jonathan Vos Post, Dec 09 2007


STATUS

approved



