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A355790 Numbers that can be written as the product of two divisors greater than 1 such that the number is contained in the string concatenation of the divisors.

%I A355790 #25 Jul 29 2022 09:55:41
%S A355790 64,95,110,210,325,510,624,640,664,950,995,1010,1100,1110,3250,3325,
%T A355790 5134,6240,6400,6640,6664,7125,7616,8145,9500,9950,9995,11000,11100,
%U A355790 11110,20100,21052,21175,25100,26208,32500,33250,33325,35126,50100,51020,51204,51340,57125,62400,64000,65114
%N A355790 Numbers that can be written as the product of two divisors greater than 1 such that the number is contained in the string concatenation of the divisors.
%H A355790 Scott R. Shannon, <a href="/A355790/a355790_1.txt">Divisor product of the first 232 terms</a>. These are all the numbers up to 50000000.
%e A355790 64 is a term as 64 = 16 * 4 and "16" + "4" = "164" contains "64".
%e A355790 65114 is a term as 65114 = 4651 * 14 and "4651" + "14" = "465114" contains "65114".
%e A355790 See the attached text file for other examples.
%o A355790 (Python)
%o A355790 from sympy import divisors
%o A355790 def ok(n):
%o A355790     s, divs = str(n), divisors(n)[1:-1]
%o A355790     return any(s in str(d)+str(n//d) for d in divs)
%o A355790 print([k for k in range(1, 10**5) if ok(k)]) # _Michael S. Branicky_, Jul 27 2022
%Y A355790 Cf. A355791 (base-2), A030190, A210959, A027750, A355852, A339144, A341035, A342127, A027748, A048991, A330027, A077293.
%K A355790 nonn,base
%O A355790 1,1
%A A355790 _Scott R. Shannon_, Jul 17 2022