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Number of permutations s_1,s_2,...,s_n of 1,2,...,n with s_1 = 4 and such that for all j=1,2,...,n, s_j divides Sum_{i=1..j} s_i.
4

%I #7 Feb 05 2019 18:45:19

%S 0,0,0,1,2,2,2,0,0,0,0,1,1,0,1,1,1,0,0,0,0,0,0,6,8,3,14,12,18,13,14,6,

%T 26,13,198,152,220,118,1033,807

%N Number of permutations s_1,s_2,...,s_n of 1,2,...,n with s_1 = 4 and such that for all j=1,2,...,n, s_j divides Sum_{i=1..j} s_i.

%C The beginning elements of the permutation are 4, (either 1 or 2), ...

%C The total number of permutations with this property is given in A067957.

%H Matthijs Coster, <a href="http://www.coster.demon.nl/sequences.htm">Sequences</a>

%H Matthijs Coster, <a href="http://www.nieuwarchief.nl/serie5/pdf/naw5-2002-03-1-092.pdf">Problem 2001/3-A of the Universitaire Wiskunde Competitie</a>, Nieuw Arch. Wisk. 5/3 (2002), 92-94.

%Y Cf. A067957, A093313, A093315.

%K nonn,more

%O 1,5

%A _Matthijs Coster_, Apr 26 2004