# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a124073 Showing 1-1 of 1 %I A124073 #15 Nov 09 2020 00:08:14 %S A124073 0,0,1824,3662976,18743463360,206032439164800,4316868116405748960, %T A124073 157846181105000772889344,9416135162778291726755147136, %U A124073 869099332136838873667455070091520,118924204222864960529120670496333629600,23292190275693669075772234927951426886017920 %N A124073 Number of permutations of n distinct letters (ABCD...) each of which appears 4 times with one fixed point. %F A124073 a(n) = A059060(n, 1). - _Joerg Arndt_, Nov 08 2020 %e A124073 A059060 as a triangle: %e A124073 1 %e A124073 0, "0", 0, 0, 1 %e A124073 1, "0", 16, 0, 36, 0, 16, 0, 1 %e A124073 346, "1824", 4536, 7136, 7947, 6336, 3936, 1728, 684, 128, 48, 0, 1 %e A124073 748521, "3662976", 8607744, 12880512, 13731616, 11042688, 6928704, 3458432, 1395126, 453888, 122016, 25344, 4824, 512, 96, 0, 1 %e A124073 3993445276, "18743463360", 42506546320, 61907282240, 64917874125, 52087325696, 33176621920, 17181584640, 7352761180, 2628808000, 790912656, 201062080, 43284010, 7873920, 1216000, 154496, 17640, 1280, 160, 0, 1 %p A124073 p := (x, k)->k!^2*sum(x^j/((k-j)!^2*j!), j=0..k); %p A124073 R := (x, n, k)->p(x, k)^n; %p A124073 f := (t, n, k)->sum(coeff(R(x, n, k), x, j)*(t-1)^j*(n*k-j)!, j=0..n*k); %p A124073 # copied from A059060 %p A124073 seq(coeff(f(t, n, 4), t, 1)/4!^n, n=1..12); %Y A124073 Cf. A059060. %K A124073 nonn,uned %O A124073 1,3 %A A124073 _Zerinvary Lajos_, Nov 05 2006 %E A124073 Offset corrected by _Joerg Arndt_, Nov 08 2020 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE