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 A103918 #12 Dec 25 2017 03:45:55 %S A103918 1,55,4214,463490,70548511,14302100449,3737959987644,1226167891984980, %T A103918 493798190899900941,239688442525550848731,138076392637292961502674, %U A103918 93162656724001697704101750,72792816042947595318479356875 %N A103918 Column k=4 sequence (without zero entries) of table A060524. %C A103918 a(n) = sum over all M2(2*n+4,k), k from {1..p(2*n+4)} restricted to partitions with exactly four odd and any nonnegative number of even parts. p(2*n+4)= A000041(2*n+4) (partition numbers) and for the M2-multinomial numbers in A-St order see A036039(2*n+4,k). - _Wolfdieter Lang_, Aug 07 2007 %F A103918 E.g.f. (with alternating zeros): A(x) = (d^4/dx^4)a(x) with a(x):=(1/(sqrt(1-x^2))*(log(sqrt((1+x)/(1-x))))^4)/4!. %e A103918 Multinomial representation for a(2): partitions of 2*2+4=8 with four odd parts: (1^3,5) with A-St position k=11; (1^2,3^2) with k=13; (1^4,4) with k=16; (1^3,2,3) with k=17 and (1^4,2^2) with k=20. The M2 numbers for these partitions are 1344, 1120, 420, 1120, 210 adding up to 4214 = a(2). %K A103918 nonn,easy %O A103918 0,2 %A A103918 _Wolfdieter Lang_, Feb 24 2005