|
| |
|
|
A024556
|
|
Odd squarefree composite numbers.
|
|
5
| |
|
|
15, 21, 33, 35, 39, 51, 55, 57, 65, 69, 77, 85, 87, 91, 93, 95, 105, 111, 115, 119, 123, 129, 133, 141, 143, 145, 155, 159, 161, 165, 177, 183, 185, 187, 195, 201, 203, 205, 209, 213, 215, 217, 219, 221, 231, 235, 237, 247, 249, 253, 255, 259, 265, 267, 273
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| Composite numbers n such that sum(k=1,n-1,floor(k^3/n)) = (1/4)*(n-2)*(n^2-1) (equality holds also for all primes) - Benoit Cloitre (benoit7848c(AT)orange.fr), Dec 08 2002
|
|
|
LINKS
| Zak Seidov, Table of n, a(n) for n = 1..11999.
Eric Weisstein's World of Mathematics, Lehmers Constant
Eric Weisstein's World of Mathematics, Prime Sums
|
|
|
MATHEMATICA
| Complement[Select[Range[3, 281, 2], SquareFreeQ], Prime[Range[PrimePi[281]]]] (* From Harvey P. Dale, Jan 26, 2011 *)
|
|
|
CROSSREFS
| Cf. A046388, A078837.
Sequence in context: A061346 A046388 A098905 * A146166 A056913 A002557
Adjacent sequences: A024553 A024554 A024555 * A024557 A024558 A024559
|
|
|
KEYWORD
| nonn,easy
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), May 22 2000
|
|
|
EXTENSIONS
| More terms from James A. Sellers (sellersj(AT)math.psu.edu), May 22 2000
|
| |
|
|
