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A055224 a(1) = 1, a(n) = number of a(k) with 1 <= k <= n-1 such that a(k) divides a(n-k).

%I A055224 #13 Jul 02 2025 16:01:59
%S A055224 1,1,2,2,2,3,4,5,4,4,3,5,4,5,3,6,7,4,5,8,6,9,6,5,6,9,10,8,5,6,10,9,8,
%T A055224 6,6,10,11,12,9,8,13,5,11,8,8,11,6,15,7,14,11,5,13,13,10,10,5,13,8,14,
%U A055224 10,7,12,13,13,12,8,11,12,9,12,14,12,8,8,15,15,12,14,12,14,15,13,19,15,12
%N A055224 a(1) = 1, a(n) = number of a(k) with 1 <= k <= n-1 such that a(k) divides a(n-k).
%H A055224 Rémy Sigrist, <a href="/A055224/b055224.txt">Table of n, a(n) for n = 1..10000</a>
%e A055224 a(10) = 4 because a(1)|a(9), a(2)|a(8), a(3)|a(7), a(5)|a(5).
%o A055224 (PARI) a = vector(86); for (n=1, #a, a[n] = if (n==1, 1, sum(k=1, n-1, a[n-k]%a[k]==0)); print1 (a[n] ", ")) \\ _Rémy Sigrist_, Jul 27 2018
%K A055224 nonn
%O A055224 1,3
%A A055224 _Leroy Quet_, Jun 20 2000
%E A055224 More terms from _James Sellers_, Jul 04 2000