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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A286763 Numbers that appear in A195441 at least once for two consecutive indices. 5
 1, 30, 210, 330, 2310, 3990, 6090, 14790, 43890, 66990, 82110, 125970, 144210, 181830, 881790, 1009470, 1067430, 1217370, 2284590, 2381190, 17687670, 18888870, 26265030, 35068110, 39544890, 47763870, 115223790, 127652070, 406816410, 497668710, 741110370, 1024748670 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The sequence is infinite; see Cor. 3 in "The denominators of power sums of arithmetic progressions". - Bernd C. Kellner and Jonathan Sondow, May 24 2017 LINKS Table of n, a(n) for n=1..32. Bernd C. Kellner, On a product of certain primes, J. Number Theory 179 (2017), 126-141; arXiv:1705.04303 [math.NT], 2017. Bernd C. Kellner and Jonathan Sondow, Power-Sum Denominators, Amer. Math. Monthly 124 (2017), 695-709; arXiv:1705.03857 [math.NT], 2017. Bernd C. Kellner and Jonathan Sondow, The denominators of power sums of arithmetic progressions, Integers 18 (2018), Article #A95, 17 pp.; arXiv:1705.05331 [math.NT], 2017. EXAMPLE A195441(21) = A195441(22) = 30, so 30 is in the sequence. - Jonathan Sondow, Dec 11 2018 MATHEMATICA Take[#, 32] &@ Union@ SequenceCases[ Table[ Denominator[ Together[ (BernoulliB[n + 1, x] - BernoulliB[n + 1])]], {n, 0, 2000}], w_ /; And[SameQ @@ w, Length@ w >= 2]][[All, 1]] (* Michael De Vlieger, Sep 22 2017, after Jonathan Sondow at A195441 *) PROG (Julia) function A286763_search() A = fmpz[]; a = fmpz(0) for n in 0:10000 u = A195441(n) a == u && push!(A, a) a = u end S = sort([a for a in Set(A)]) S[1:32] end println(A286763_search()) CROSSREFS Cf. A195441, A286516, A286762. Sequence in context: A181629 A346245 A129499 * A347828 A069965 A215627 Adjacent sequences: A286760 A286761 A286762 * A286764 A286765 A286766 KEYWORD nonn,changed AUTHOR Peter Luschny, May 14 2017 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 15 13:51 EDT 2024. Contains 375938 sequences. (Running on oeis4.)