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A140151
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a(1)=1, a(n)=a(n-1)+n^2 if n odd, a(n)=a(n-1)+ n^5 if n is even.
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1
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1, 33, 42, 1066, 1091, 8867, 8916, 41684, 41765, 141765, 141886, 390718, 390887, 928711, 928936, 1977512, 1977801, 3867369, 3867730, 7067730, 7068171, 12221803, 12222332, 20184956, 20185581, 32066957, 32067686, 49278054, 49278895
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| a(n)=a(n-1)+{[1-(-1)^n]/2}*n^2+{[1+(-1)^n]/2}*n^5, with a(1)=1 a(n)= (-1/8)-(1/4)*(-1)^n*n+(1/8)*(-1)^n+(1/6)*n^3-(7/8)*(-1)^n*n^2+(5/24)*n^2+(1/12)*n+(1/12)*n^6+(1/4 )*(-1)^n*n^5+(1/4)*n^5+(5/8)*(-1)^n*n^4+(5/24)*n^4, with n>=1 - Paolo P. Lava (paoloplava(AT)gmail.com), Jun 06 2008
G.f.: x*(-1-32*x-3*x^2-832*x^3+14*x^4-2112*x^5-14*x^6-832*x^7+3*x^8-32*x^9+x^10 )/((1+x)^6*(x-1)^7). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 22 2009]
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MATHEMATICA
| a = {}; r = 2; s = 5; Do[k = 0; Do[k = k + (Sin[Pi m/2]^2) m^r + (Cos[Pi m/2]^2) m^s, {m, 1, n}]; AppendTo[a, k], {n, 1, 100}]; a (*Artur Jasinski*)
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CROSSREFS
| Cf. A000027, A000217, A000330, A000537, A000538, A000539, A136047, A140113.
Sequence in context: A168311 A045241 A046041 * A196579 A121993 A050875
Adjacent sequences: A140148 A140149 A140150 * A140152 A140153 A140154
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KEYWORD
| nonn
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AUTHOR
| Jasinski Artur (grafix(AT)csl.pl), May 12 2008
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