A174902 Denominator of 1 - 1/n^2, using 0 at the pole where n=0.

1, 0, 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256, 289, 324, 361, 400, 441, 484, 529, 576, 625, 676, 729, 784, 841, 900, 961, 1024, 1089, 1156, 1225, 1296, 1369, 1444, 1521, 1600, 1681, 1764, 1849, 1936, 2025

Offset

-1,4

Comments

From Lyman antispectrum of hydrogen.

Links

Table of n, a(n) for n=-1..45.

Index entries for linear recurrences with constant coefficients, signature (3,-3,1).

Formula

a(n) = A000290(n), n>=0.

Prog

(PARI) a(n)=n^2 \\ Charles R Greathouse IV, Nov 26 2012

Crossrefs

Main sequence is A000290.

Sequence in context: A069821 A331221 A174452 * A000290 A162395 A253909

Adjacent sequences: A174899 A174900 A174901 * A174903 A174904 A174905

Keyword

nonn,easy,less

Author

Paul Curtz, Dec 02 2010

Status

approved