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 A177890 15-gonal (or pentadecagonal) pyramidal numbers:  a(n) = n*(n+1)*(13*n-10)/6. 2
 0, 1, 16, 58, 140, 275, 476, 756, 1128, 1605, 2200, 2926, 3796, 4823, 6020, 7400, 8976, 10761, 12768, 15010, 17500, 20251, 23276, 26588, 30200, 34125, 38376, 42966, 47908, 53215, 58900, 64976, 71456, 78353, 85680, 93450, 101676, 110371, 119548, 129220 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Also a(n) = (15-m)*A000292(n-1) + n*(n+1)*((m-2)*n - (m-5))/6 being n*(n+1)*((m-2)*n - (m-5))/6 a m-gonal pyramidal number (1 < m < 15). For m=6, a(n) = 9*A000292(n-1) + A002412(n). Inverse binomial transform of this sequence: 0, 1, 14, 13, 0, 0 (0 continued). REFERENCES E. Deza and M. M. Deza, Figurate numbers, World Scientific Publishing (2012), page 93 (thirteenth row of the table). LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..1000 Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1). FORMULA G.f.: x*(1+12*x)/(1-x)^4. a(n) = Sum_{i=0..n} A051867(i). a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). - Vincenzo Librandi, Jul 04 2012 a(n) = Sum_{i=0..n-1} (n-i)*(13*i+1), with a(0)=0. - Bruno Berselli, Feb 10 2014 E.g.f.: x*(6 + 42*x + 13*x^2)*exp(x)/6. - G. C. Greubel, Aug 30 2019 MAPLE seq(n*(n+1)*(13*n-10)/6, n=0..40); # G. C. Greubel, Aug 30 2019 MATHEMATICA CoefficientList[Series[x*(1+12*x)/(1-x)^4, {x, 0, 40}], x] (* Vincenzo Librandi, Jul 04 2012 *) Table[n*(n-1)*(13*n-23)/6, {n, 40}] (* G. C. Greubel, Aug 30 2019 *) PROG (MAGMA) I:=[0, 1, 16, 58]; [n le 4 select I[n] else 4*Self(n-1)-6*Self(n-2) +4*Self(n-3)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Jul 04 2012 (MAGMA) [n*(n+1)*(13*n-10)/6: n in [0..40]]; // G. C. Greubel, Aug 30 2019 (PARI) vector(40, n, n*(n-1)*(13*n-23)/6) \\ G. C. Greubel, Aug 30 2019 (Sage) [n*(n+1)*(13*n-10)/6 for n in (0..40)] # G. C. Greubel, Aug 30 2019 (GAP) List([0..40], n-> n*(n+1)*(13*n-10)/6); # G. C. Greubel, Aug 30 2019 CROSSREFS Cf. similar sequences listed in A237616. Sequence in context: A235517 A253428 A005905 * A225922 A235510 A220974 Adjacent sequences:  A177887 A177888 A177889 * A177891 A177892 A177893 KEYWORD nonn,easy AUTHOR Bruno Berselli, Dec 14 2010 STATUS approved

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Last modified December 6 22:42 EST 2021. Contains 349567 sequences. (Running on oeis4.)