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 A189043 For all permutations of [1..n]: number of distinct values taken by sum(k=1..n, k^2 * pi(k) ). 0
 1, 2, 6, 23, 89, 232, 437, 747, 1191, 1806, 2631, 3709, 5087, 6816 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE The permutations of 4 elements and the respective sums are [ 1 2 3 4 ] 100 [ 1 2 4 3 ]  93 [ 1 3 2 4 ]  95 [ 1 3 4 2 ]  81 [ 1 4 2 3 ]  83 [ 1 4 3 2 ]  76 [ 2 1 3 4 ]  97 [ 2 1 4 3 ]  90 [ 2 3 1 4 ]  87 [ 2 3 4 1 ]  66 [ 2 4 1 3 ]  75 [ 2 4 3 1 ]  61 [ 3 1 2 4 ]  89 [ 3 1 4 2 ]  75  // same as [ 2 4 1 3 ] [ 3 2 1 4 ]  84 [ 3 2 4 1 ]  63 [ 3 4 1 2 ]  60 [ 3 4 2 1 ]  53 [ 4 1 2 3 ]  74 [ 4 1 3 2 ]  67 [ 4 2 1 3 ]  69 [ 4 2 3 1 ]  55 [ 4 3 1 2 ]  57 [ 4 3 2 1 ]  50 All values except 75 are unique, so a(4) = 4!-1 = 23. CROSSREFS Cf. A126972 (sum k*pi(k)). Sequence in context: A247211 A150275 A150276 * A228392 A190910 A150277 Adjacent sequences:  A189040 A189041 A189042 * A189044 A189045 A189046 KEYWORD nonn,more AUTHOR Joerg Arndt, Apr 22 2011 EXTENSIONS Corrected terms (error pointed out by Alois P. Heinz), Joerg Arndt, Apr 28 2011. a(14) from Alois P. Heinz, Apr 28 2011 STATUS approved

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