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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.
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%I #25 Jul 29 2022 09:55:41

%S 64,95,110,210,325,510,624,640,664,950,995,1010,1100,1110,3250,3325,

%T 5134,6240,6400,6640,6664,7125,7616,8145,9500,9950,9995,11000,11100,

%U 11110,20100,21052,21175,25100,26208,32500,33250,33325,35126,50100,51020,51204,51340,57125,62400,64000,65114

%N 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 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 64 is a term as 64 = 16 * 4 and "16" + "4" = "164" contains "64".

%e 65114 is a term as 65114 = 4651 * 14 and "4651" + "14" = "465114" contains "65114".

%e See the attached text file for other examples.

%o (Python)

%o from sympy import divisors

%o def ok(n):

%o s, divs = str(n), divisors(n)[1:-1]

%o return any(s in str(d)+str(n//d) for d in divs)

%o print([k for k in range(1, 10**5) if ok(k)]) # _Michael S. Branicky_, Jul 27 2022

%Y Cf. A355791 (base-2), A030190, A210959, A027750, A355852, A339144, A341035, A342127, A027748, A048991, A330027, A077293.

%K nonn,base

%O 1,1

%A _Scott R. Shannon_, Jul 17 2022