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 A109385 #12 Dec 30 2023 17:40:10
%S A109385 1,2,6,13,32,92,218,576,1698,4300,11770,34914,91105,254438,759488,
%T A109385 2030618,5746274,17189858,46698068,133334440,399479982,1099206284,
%U A109385 3159208516,9470895658,26313455375,76003857800,227935595004,638304618462,1850933165704,5551816202580
%N A109385 Maximum number of prime implicants of a symmetric function of n Boolean variables.
%C A109385 Many people have conjectured that this sequence is equal to A003039. Certainly it is a lower bound. An upper bound is given in A109388.
%D A109385 Yoshihide Igarashi, An improved lower bound on the maximum number of prime implicants, Transactions of the IECE of Japan, E62 (1979), 389-394.
%D A109385 A. P. Vikulin, Otsenka chisla kon"iunktsii v sokrashchennyh DNF [An estimate of the number of conjuncts in reduced disjunctive normal forms], Problemy Kibernetiki 29 (1974), 151-166.
%e A109385 a(10) = 4300 because the symmetric function S_{1,2,4,5,6,7,9,10}(x_1,...,x_{10}) has 90+4200+10 prime implicants.
%t A109385 b[m_, n_] := If[m < 0, 0, Multinomial[Floor[m/2], Ceiling[m/2], n - m] + b[Ceiling[m/2] - 2, n]]; a[n_] := Multinomial[Floor[n/3], Floor[(n + 1)/3], Floor[(n + 2)/3]] + b[Floor[(n - 4)/3], n] + b[Floor[(n - 5)/3], n]; Table[a[n], {n, 35}]
%Y A109385 Cf. A003039, A109388, A109452.
%K A109385 easy,nonn
%O A109385 1,2
%A A109385 _Don Knuth_, Aug 25 2005
%E A109385 Extended by _T. D. Noe_ using the Mma program, Jan 15 2012