cp's OEIS Frontend

A189043 For all permutations of [1..n]: number of distinct values taken by sum(k=1..n, k^2 * pi(k) ).

%I A189043 #47 Oct 15 2021 19:49:02
%S A189043 1,2,6,23,89,232,437,747,1191,1806,2631,3709,5087,6816
%N A189043 For all permutations of [1..n]: number of distinct values taken by sum(k=1..n, k^2 * pi(k) ).
%e A189043 The permutations of 4 elements and the respective sums are
%e A189043 [ 1 2 3 4 ] 100
%e A189043 [ 1 2 4 3 ]  93
%e A189043 [ 1 3 2 4 ]  95
%e A189043 [ 1 3 4 2 ]  81
%e A189043 [ 1 4 2 3 ]  83
%e A189043 [ 1 4 3 2 ]  76
%e A189043 [ 2 1 3 4 ]  97
%e A189043 [ 2 1 4 3 ]  90
%e A189043 [ 2 3 1 4 ]  87
%e A189043 [ 2 3 4 1 ]  66
%e A189043 [ 2 4 1 3 ]  75
%e A189043 [ 2 4 3 1 ]  61
%e A189043 [ 3 1 2 4 ]  89
%e A189043 [ 3 1 4 2 ]  75  // same as [ 2 4 1 3 ]
%e A189043 [ 3 2 1 4 ]  84
%e A189043 [ 3 2 4 1 ]  63
%e A189043 [ 3 4 1 2 ]  60
%e A189043 [ 3 4 2 1 ]  53
%e A189043 [ 4 1 2 3 ]  74
%e A189043 [ 4 1 3 2 ]  67
%e A189043 [ 4 2 1 3 ]  69
%e A189043 [ 4 2 3 1 ]  55
%e A189043 [ 4 3 1 2 ]  57
%e A189043 [ 4 3 2 1 ]  50
%e A189043 All values except 75 are unique, so a(4) = 4!-1 = 23.
%Y A189043 Cf. A126972 (sum k*pi(k)).
%K A189043 nonn,more
%O A189043 1,2
%A A189043 _Joerg Arndt_, Apr 22 2011
%E A189043 Corrected terms (error pointed out by _Alois P. Heinz_), _Joerg Arndt_, Apr 28 2011.
%E A189043 a(14) from _Alois P. Heinz_, Apr 28 2011