This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A036410 #45 Dec 17 2021 01:22:36 %S A036410 1,1,1,2,3,3,5,6,7,9,11,12,15,17,19,22,25,27,31,34,37,41,45,48,53,57, %T A036410 61,66,71,75,81,86,91,97,103,108,115,121,127,134,141,147,155,162,169, %U A036410 177,185,192,201,209,217,226,235,243,253,262,271,281 %N A036410 G.f.: (1+x^6)/((1-x)*(1-x^3)*(1-x^4)). %H A036410 G. Nebe, E. M. Rains and N. J. A. Sloane, <a href="http://neilsloane.com/doc/cliff2.html">Self-Dual Codes and Invariant Theory</a>, Springer, Berlin, 2006. %H A036410 <a href="/index/Mo#Molien">Index entries for Molien series</a> %H A036410 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,0,-1,-1,1). %F A036410 a(n) = ceiling((n+1)^2/12). %F A036410 From _R. J. Mathar_, Jan 22 2011: (Start) %F A036410 a(n) = a(n-1) + a(n-2) - a(n-4) - a(n-5) + a(n-6). %F A036410 G.f.: ( -1-x^4+x^2 ) / ( (1+x)*(1+x+x^2)*(x-1)^3 ). (End) %F A036410 From _R. J. Mathar_, Jan 14 2021: (Start) %F A036410 a(n) - a(n-1) = A008612(n). %F A036410 Empirical: a(n) + a(n+1) = A266542(n). %F A036410 72*a(n) = 6*n^2 + 12*n + 47 + 9*(-1)^n + 16*A061347(n+1). (End) %F A036410 a(n) = a(-2-n) for all n in Z. - _Michael Somos_, Dec 16 2021 %e A036410 G.f. = 1 + x + x^2 + 2*x^3 + 3*x^4 + 3*x^5 + 5*x^6 + 6*x^7 + ... - _Michael Somos_, Dec 16 2021 %t A036410 a[ n_] := Ceiling[(n + 1)^2/12]; (* _Michael Somos_, Dec 16 2021 *) %o A036410 (Maxima) makelist(coeff(taylor((1+x^6)/((1-x)*(1-x^3)*(1-x^4)),x,0,n),x,n),n,0,57); /* _Bruno Berselli_, May 30 2011 */ %o A036410 (PARI) {a(n) = (n^2 + 2*n)\12 + 1}; /* _Michael Somos_, Dec 16 2021 */ %Y A036410 Cf. A008724, A001399. %K A036410 nonn,easy %O A036410 0,4 %A A036410 _N. J. A. Sloane_