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

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]];
Table[a[n], {n, 3, rows}] (* Jean-François Alcover, May 06 2022 *)

Crossrefs

Sequence in context: A349640 A111842 A247883 * A062632 A116892 A201481

Adjacent sequences: A027455 A027456 A027457 * A027459 A027460 A027461

Keyword

nonn

Author

Olivier Gérard

Extensions

More terms from Sean A. Irvine, Nov 04 2019

Status

approved