A027458 - OEIS

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A027458

Third column of A027446.

2, 7, 47, 57, 459, 1023, 3349, 3601, 42131, 44441, 605453, 631193, 655217, 1355479, 23763863, 24444543, 476698557, 488338185, 499423545, 510005025, 11962908135, 12186001005, 62000850801, 63030510201, 192066102203, 194934439103, 5733412167187, 5811048485947

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OFFSET

3,1

LINKS

Table of n, a(n) for n=3..30.

FORMULA

Numerators of sequence a[ 3, n ] in (a[ i, j ])^2 where a[ i, j ] = 1/i if j<=i, 0 if j>i

MATHEMATICA

rows = 30;

M = MatrixPower[Table[If[j <= i, 1/i, 0], {i, 1, rows}, {j, 1, rows}], 2];

T = Table[M[[n]]*LCM @@ Denominator[M[[n]]], {n, 1, rows}];

a[n_] := T[[n, 3]];