The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A084970 Numbers whose smallest prime factor is 13. 13
 13, 169, 221, 247, 299, 377, 403, 481, 533, 559, 611, 689, 767, 793, 871, 923, 949, 1027, 1079, 1157, 1261, 1313, 1339, 1391, 1417, 1469, 1651, 1703, 1781, 1807, 1937, 1963, 2041, 2119, 2171, 2197, 2249, 2327, 2353, 2483, 2509, 2561, 2587, 2743, 2873 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 Index entries for linear recurrences with constant coefficients, order 481. FORMULA a(n) = a(n-480) + 30030 = a(n-1) + a(n-480) - a(n-481). - Charles R Greathouse IV, Nov 19 2014 Lim_{n->infinity} a(n)/n = A038111(6)/A038110(6) = 1001/16 = 62.5625. - Vladimir Shevelev, Jan 20 2015 a(n) = 13*A008365(n). EXAMPLE a(2) = 13*13, a(3) = 13*17. MATHEMATICA Select[ 13Range@ 225, GCD[#, 2310] == 1 &] (* Robert G. Wilson v, Dec 18 2014 *) PROG (PARI) is(n)=n%13==0 && gcd(n, 2310)==1 \\ Charles R Greathouse IV, Nov 19 2014 CROSSREFS Sixth row of A083140. Cf. A084967 (5), A084968 (7), A084969 (11), A332799 (17), A332798 (19), A332797 (23), A008365 (13-rough numbers). Sequence in context: A171318 A078362 A157381 * A209226 A208503 A207696 Adjacent sequences: A084967 A084968 A084969 * A084971 A084972 A084973 KEYWORD nonn,easy AUTHOR Robert G. Wilson v, Jun 15 2003 EXTENSIONS More terms from David Wasserman, Oct 19 2004 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 29 23:18 EDT 2023. Contains 365781 sequences. (Running on oeis4.)