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%I #8 Sep 14 2016 05:59:55
%S 1,4,4,8,4,12,4,10,9,16,4,16,4,20,8,12,6,24,8,16,8,16,4,40,6,16,8,16,
%T 8,40,8,14,8,24,8,24,4,24,16,20,6,32,4,32,24,20,4,24,12,24,8,32,4,56,
%U 8,20,12,16,12,32,4,20,24,32,8,48,4,16,16,48,4,30,8
%N Number of divisors of the n-th octagonal number.
%H Colin Barker, <a href="/A276681/b276681.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A000005(A000567(n)).
%e a(4) = 8 because the 4th octagonal number is 40, which has 8 divisors: 1,2,4,5,8,10,20,40.
%o (PARI)
%o pg(m, n) = (n^2*(m-2)-n*(m-4))/2 \\ n-th m-gonal number
%o vector(150, n, numdiv(pg(8,n)))
%Y Cf. A000005, A000567.
%Y Cf. A063440 (m=3), A048691 (m=4), A276678 (m=5), A276679 (m=6), A276680 (m=7), A276682 (m=9), A276683 (m=10).
%K nonn
%O 1,2
%A _Colin Barker_, Sep 13 2016
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