This site is supported by donations to The OEIS Foundation.

 Annual Appeal: Please make a donation to keep the OEIS running. In 2018 we replaced the server with a faster one, added 20000 new sequences, and reached 7000 citations (often saying "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A133151 a(n) = smallest k such that A000326(n+1) = A000326(n) + (A000326(n) mod k), or 0 if no such k exists. 3
 0, 0, 0, 0, 19, 32, 24, 67, 89, 38, 71, 173, 69, 61, 71, 109, 373, 211, 79, 529, 587, 72, 89, 779, 283, 461, 499, 359, 1159, 311, 111, 1423, 1517, 269, 857, 1817, 641, 127, 134, 251, 2377, 1249, 138, 2749, 2879, 251, 787, 173, 381, 1787, 1861, 1291 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS a(n) is the "weight" of pentagonal numbers (A000326). The decomposition of pentagonal numbers into weight * level + gap is A000326(n) = a(n) * A184751(n) + A016777(n) if a(n) > 0. LINKS Remi Eismann, Table of n, a(n) for n = 1..1000 EXAMPLE For n = 1 we have A000326(n) = 1, A000326(n+1) = 5; there is no k such that 5 - 1 = 4 = (1 mod k), hence a(1) = 0. For n = 5 we have A000326(n) = 35, A000326(n+1) = 51; 19 is the smallest k such that 51 - 35 = 16 = (35 mod k), hence a(5) = 19. For n = 18 we have A000326(n) = 477, A000326(n+1) = 532; 211 is the smallest k such that 532 - 477 = 55 = (477 mod k), hence a(18) = 211. CROSSREFS Cf. A000326, A016777, A184751, A184750, A117078, A117563, A001223, A118534. Sequence in context: A146816 A146659 A160220 * A184750 A101063 A061962 Adjacent sequences:  A133148 A133149 A133150 * A133152 A133153 A133154 KEYWORD nonn AUTHOR Rémi Eismann, Sep 22 2007 - Jan 21 2011 STATUS approved

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

Last modified December 17 07:54 EST 2018. Contains 318192 sequences. (Running on oeis4.)