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 A143238 a(n) = A000203(n) * A024916(n). 1

%I #6 Feb 26 2020 15:58:00

%S 1,12,32,105,126,396,328,840,897,1566,1188,3556,1974,3960,4536,6820,

%T 4284,10803,5940,14238,11872,14652,10344,29460,16182,23688,24160,

%U 36960,20700,54864,25408,53991,43440,51786,48336,99918,43168,71760,70112,120780,58128,142080

%N a(n) = A000203(n) * A024916(n).

%F a(n) = A000203(n) * A024916(n) = row sums of triangle A143237.

%e a(4) = 105 = A000203(4) * A024916(4) = 7 * 15.

%e a(4) = 105 = sum of row 4 terms of triangle A143237: (7, + 21, + 28 + 49).

%t sigma = Table[DivisorSigma[1, n], {n, 1, 50}]; sigma * Accumulate[sigma] (* _Amiram Eldar_, Feb 26 2020 *)

%Y Cf. A000203, A024916, A143237.

%K nonn

%O 1,2

%A _Gary W. Adamson_, Aug 01 2008

%E More terms from _Amiram Eldar_, Feb 26 2020

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Last modified September 30 02:05 EDT 2023. Contains 365781 sequences. (Running on oeis4.)