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 A319278 Square array sigma_k(n) read down antidiagonals: sum of the k-th powers of the divisors of n. 1

%I

%S 1,1,3,1,5,4,1,9,10,7,1,17,28,21,6,1,33,82,73,26,12,1,65,244,273,126,

%T 50,8,1,129,730,1057,626,252,50,15,1,257,2188,4161,3126,1394,344,85,

%U 13,1,513,6562,16513,15626,8052,2402,585,91,18,1,1025,19684,65793,78126,47450,16808,4369,757,130,12

%N Square array sigma_k(n) read down antidiagonals: sum of the k-th powers of the divisors of n.

%C Equals the square array A082771 without its first column.

%F sigma_k(n) = sum_{d|n} d^k.

%e The array starts in row n=1 with columns k>=1 as:

%e 1 1 1 1 1 1 1 1

%e 3 5 9 17 33 65 129 257

%e 4 10 28 82 244 730 2188 6562

%e 7 21 73 273 1057 4161 16513 65793

%e 6 26 126 626 3126 15626 78126 390626

%e 12 50 252 1394 8052 47450 282252 1686434

%e 8 50 344 2402 16808 117650 823544 5764802

%e 15 85 585 4369 33825 266305 2113665 16843009

%Y Columns: A000203, A001157, A001158, A001159.

%Y Rows: A000012, A000051, A034472, A001576, A034474, A034488.

%Y Cf. A082771, A023887 (diagonal), A319194 (partial column sums).

%K nonn,tabl,easy

%O 1,3

%A _R. J. Mathar_, Sep 16 2018

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Last modified August 18 13:58 EDT 2019. Contains 326100 sequences. (Running on oeis4.)