Search: id:A145919
Results 1-1 of 1 results found.

%I A145919
%S A145919 0,0,0,0,1,2,3,5,7,9,12,15,18,22,26,30,35,40,45,51,57,63,70,77,
%T A145919 84,92,100,108,117,126,135,145,155,165,176,187,198,210,222,234,
%U A145919 247,260,273,287,301,315,330,345,360,376,392,408,425,442,459,477
%V A145919 0,0,0,0,1,2,-3,5,7,-9,12,15,-18,22,26,-30,35,40,-45,51,57,-63,70,77,
%W A145919 -84,92,100,-108,117,126,-135,145,155,-165,176,187,-198,210,222,-234,
%X A145919 247,260,-273,287,301,-315,330,345,-360,376,392,-408,425,442,-459,477
%N A145919 A000332(n) = a(n)(3*a(n) - 1)/2.
%C A145919 As the formula in the description shows, all members of A000332 belong 
               to the generalized pentagonal sequence (A001318). A001318 also lists 
               all nonnegative numbers that belong to A145919.
%H A145919 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               PentagonalNumber.html">Pentagonal Number</a>.
%H A145919 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               PentatopeNumber.html">Pentatope Number</a>.
%F A145919 a(n+3)= A001840(n) when 3 does not divide n, A001840(n)*-1 otherwise.
%F A145919 After first two zeros, this sequence consists of all values of A001318(n) 
               and A045943(n)*(-1), n>=0, sorted in order of increasing absolute 
               value.
%F A145919 G.f.:(-x^4*(x^4+2*x^3-3*x^2+2*x+1))/((x-1)^3*(1+x^2+x)^3) [From Maksym 
               Voznyy (voznyy(AT)mail.ru), Jul 27 2009]
%e A145919 a(6) = -3 and A000332(6) = (-3)(-10)/2 = 15.
%Y A145919 Cf. A000326, A145920.
%Y A145919 Sequence in context: A024195 A071423 A062781 this_sequence A058937 A130518 
               A001840
%Y A145919 Adjacent sequences: A145916 A145917 A145918 this_sequence A145920 A145921 
               A145922
%K A145919 easy,sign
%O A145919 0,6
%A A145919 Matthew Vandermast (ghodges14(AT)comcast.net), Oct 28 2008

Search completed in 0.001 seconds