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 A005340 M4903 #52 Apr 03 2025 10:47:32 %S A005340 1,13,76,295,889,2188,4652,8891,15686,26011,41056,62251,91291,130162, %T A005340 181168,246959,330560,435401,565348,724735,918397,1151704,1430596, %U A005340 1761619,2151962,2609495,3142808,3761251,4474975,5294974,6233128 %N A005340 Number of ways in which n identical balls can be distributed among 7 boxes in a row such that each pair of adjacent boxes contains at least 4 balls. %D A005340 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A005340 Vincenzo Librandi, <a href="/A005340/b005340.txt">Table of n, a(n) for n = 12..1000</a> %H A005340 D. R. Breach, <a href="/A004120/a004120.pdf">Letter to N. J. A. Sloane, Jun 1980</a> %H A005340 Philippe Flajolet, <a href="http://algo.inria.fr/libraries/autocomb/balls-html/balls.html">Balls and Urns, etc.</a>, A problem in submarine detection (solution to problem 68-16). %H A005340 M. Hayes (proposer) and D. R. Breach (solver), <a href="https://doi.org/10.1137/1012060">A combinatorial problem, Problem 68-16</a>, SIAM Rev. 12 (1970), 294-297. %H A005340 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (7, -21, 35, -35, 21, -7, 1). %F A005340 G.f.: x^12*(1 + 6*x + 6*x^2 + x^3 - 66*x^5 + 74*x^6 - 21*x^7)/(1-x)^7. - _Vladeta Jovovic_, Apr 13 2008 %t A005340 f[x_] := x^12*(1 + 6*x + 6*x^2 + x^3 - 66*x^5 + 74*x^6 - 21*x^7)/(1-x)^7; Drop[ CoefficientList[ Series[f[x], {x, 0, 42}], x], 12] (* _Jean-François Alcover_, Oct 05 2011, after _Vladeta Jovovic_ *) %t A005340 LinearRecurrence[{7,-21,35,-35,21,-7,1},{1,13,76,295,889,2188,4652,8891},40] (* _Harvey P. Dale_, Apr 03 2025 *) %Y A005340 Cf. A005337, A005338, A005339. %K A005340 nonn,easy %O A005340 12,2 %A A005340 _N. J. A. Sloane_ %E A005340 More terms from _Vladeta Jovovic_, Apr 13 2008 %E A005340 Name clarified by _Alois P. Heinz_, Oct 02 2017