cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A239048 1 plus the n-th divisor of 24.

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%I A239048 #16 Jan 01 2024 18:15:21
%S A239048 2,3,4,5,7,9,13,25
%N A239048 1 plus the n-th divisor of 24.
%C A239048 Also Coxeter number (denoted m(X)) of the Niemeier lattices X whose root systems are of pure A-type according to the ADE classification; see Ono-Rolen-Trebat paper, page 3, Table 1, Pure A-type root systems.
%D A239048 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, 3rd. ed., 1993. Table 16.1, p. 407.
%H A239048 Ken Ono, Larry Rolen, Sarah Trebat-Leder, <a href="http://arxiv.org/abs/1403.3712">Classical and umbral Moonshine: connections and p-adic properties</a>, arXiv:1403.7312v1 [math.NT]
%F A239048 a(n) = 1 + A018253(n).
%t A239048 1 + Divisors[24] (* _Wesley Ivan Hurt_, Jan 01 2024 *)
%Y A239048 Cf. A000521, A007240, A018253, A018623.
%Y A239048 A subsequence of A238839.
%K A239048 nonn,easy,fini,full
%O A239048 1,1
%A A239048 _Omar E. Pol_, Mar 18 2014