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 A095894 #29 Feb 16 2022 11:58:57
%S A095894 1,7,14,26,39,57,76,100,125,155,186,222,259,301,344,392,441,495,550,
%T A095894 610,671,737,804,876,949,1027,1106,1190,1275,1365,1456,1552,1649,1751,
%U A095894 1854,1962,2071,2185,2300,2420,2541,2667,2794,2926,3059,3197,3336,3480
%N A095894 a(2n) = 6*n^2 + 7*n + 1; a(2n+1) = 6*n^2 + 13*n + 7.
%C A095894 From _Omar E. Pol_, Jul 18 2012: (Start)
%C A095894 Positive terms of A051866 and positive terms of A049453 interleaved.
%C A095894 Also sequence found by reading the line from 1, in the direction 1, 14, ..., and the line from 7, in the direction 7, 26, ..., in the square spiral whose vertices are the generalized pentagonal numbers A001318. (End)
%H A095894 G. C. Greubel, <a href="/A095894/b095894.txt">Table of n, a(n) for n = 0..1000</a>
%H A095894 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (2,0,-2,1).
%F A095894 G.f.: ( -1-5*x ) / ( (1+x)*(x-1)^3 ). - _R. J. Mathar_, Oct 26 2011
%t A095894 LinearRecurrence[{2,0,-2,1},{1,7,14,26},60] (* _Harvey P. Dale_, Oct 13 2016 *)
%o A095894 (PARI) x='x+O('x^50); Vec((-1-5*x)/((1+x)*(x-1)^3)) \\ _G. C. Greubel_, Jun 19 2017
%Y A095894 Cf. A047225 (first differences), A049453, A051866.
%K A095894 nonn,easy
%O A095894 0,2
%A A095894 _Gary W. Adamson_, Jun 11 2004
%E A095894 Edited by _Don Reble_, Nov 16 2005