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%I #8 Jan 04 2024 01:48:37
%S 1,2,2,3,1,3,1,3,2,3,2,5,2,3,2,3,1,3,1,5,3,4,2,6,1,3,2,4,1,5,2,4,4,3,
%T 1,5,1,2,3,6,2,6,2,6,2,3,1,6,1,3,2,4,1,3,2,4,2,2,1,8,1,3,3,4,2,6,1,4,
%U 3,4,1,6,1,2,2,3,2,4,1,6,2,3,1,8,1,3,2,6,1,5,2,4,3,2,1,7,1,3,4,6,2,5,2,5,3
%N Number of divisors of n with largest digit <= 4 (base 10).
%F a(n) = A083898(n) + A083891(n) = A083900(n) - A083892(n).
%F Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = Sum_{k>=1} 1/A007091(k) = 3.92521682598923397031... . - _Amiram Eldar_, Jan 04 2024
%t a[n_] := DivisorSum[n, 1 &, Max[IntegerDigits[#]] <= 4 &]; Array[a, 100] (* _Amiram Eldar_, Jan 04 2024 *)
%Y Cf. A054055, A000005, A007091, A083891, A083892, A083898, A083900.
%K nonn,base
%O 1,2
%A _Reinhard Zumkeller_, May 08 2003
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