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%I #29 Sep 18 2024 11:05:54
%S 3,8,24,35,48,99,120,143,168,195,224,288,323,360,399,440,483,528,575,
%T 675,783,840,899,960,1088,1155,1224,1368,1443,1520,1599,1680,1763,
%U 1848,1935,2024,2115,2208,2303,2499,2600,2703,2808,2915,3024,3135
%N Numbers which are one less than a perfect square that cannot otherwise be written as a power.
%C Denominators of decimal part of zeta(2) when it is represented as a sum of geometric series: zeta(2) = 1 + Sum_{n>=0} 1/a(n). - _Andrés Ventas_, Apr 06 2021
%D W. Dunham, Euler: The Master of Us All, The Mathematical Association of America, Washington D.C., 1999, p. 66.
%D L. Euler, "Variae observationes circa series infinitas," Opera Omnia, Ser. 1, Vol. 14, pp. 216-244.
%H L. Euler, <a href="http://math.dartmouth.edu/~euler/pages/E072.html">Variae observationes circa series infinitas</a>
%H Joakim Munkhammar, <a href="https://doi.org/10.1017/mag.2020.110">The Riemann zeta function as a sum of geometric series</a>, The Mathematical Gazette (2020) Vol. 104, Issue 561, 527-530.
%F a(n) = A007916(n)^2 - 1. - _David A. Corneth_, Apr 06 2021
%o (PARI) lista(m) = {for (i=2, m, sq = i^2; if (ispower(sq) == 2, print1(sq-1, ", ")););} \\ _Michel Marcus_, Apr 17 2013
%Y Cf. A007916, A062834.
%K nonn
%O 1,1
%A _Jason Earls_, Jul 21 2001
%E More terms from _Dean Hickerson_, Jul 24 2001
%E Offset corrected by _Andrew Howroyd_, Sep 18 2024