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 A005880 Theta series of D_4 lattice with respect to edge. (Formerly M1827) 2
 2, 8, 12, 16, 26, 24, 28, 48, 36, 40, 64, 48, 62, 80, 60, 64, 96, 96, 76, 112, 84, 88, 156, 96, 114, 144, 108, 144, 160, 120, 124, 208, 168, 136, 192, 144, 148, 248, 192, 160, 242, 168, 216, 240 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 REFERENCES N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS G. C. Greubel, Table of n, a(n) for n = 0..5000 MATHEMATICA Table[2 DivisorSigma[1, 2 n + 1], {n, 0, 43}] (* Jean-François Alcover, Jul 06 2017 *) PROG (PARI) for(n=0, 30, print1(2*sigma(2*n+1), ", ")) \\ G. C. Greubel, Nov 30 2017 CROSSREFS Equals 2 * A008438. Sequence in context: A285658 A284802 A067884 * A290608 A303900 A046470 Adjacent sequences:  A005877 A005878 A005879 * A005881 A005882 A005883 KEYWORD nonn AUTHOR STATUS approved

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Last modified December 7 22:29 EST 2019. Contains 329850 sequences. (Running on oeis4.)