A234314 - OEIS

A234314

Let x(0)x(1)x(2)... x(q) denote the decimal expansion of n. Sequence lists the numbers n such that the suffix of decimal expansion x(1)x(2)... x(q) is the x(0)-th divisor of n.

%I #5 Dec 23 2013 18:48:24

%S 11,22,25,101,202,205,304,410,425,620,735,816,832,850,975,1001,2002,

%T 2005,3004,4010,5025,5125,7035,7175,8016,9024,9036,9040,9075,10001,

%U 20002,20005,30004,30025,40010,50008,60016,60020,60050,70625,80010,80016,80128,90036

%N Let x(0)x(1)x(2)... x(q) denote the decimal expansion of n. Sequence lists the numbers n such that the suffix of decimal expansion x(1)x(2)... x(q) is the x(0)-th divisor of n.

%e 735 is in the sequence because the divisors of 735 are {1, 3, 5, 7, 15, 21, 35, 49, 105, 147, 245, 735} and 35 is the 7th divisor of 735.

%p with(numtheory):for n from 1 to 100000 do:x:=convert(n,base,10):n1:=nops(x):y:=divisors(n):n2:=nops(y):a:=x[n1]: s:=sum('x[i]*10^(i-1) ', 'i'=1..n1-1):if n2>a and y[a]=s then printf(`%d, `,n):else fi:od:

%Y Cf. A234315.

%K nonn,base

%O 1,1

%A _Michel Lagneau_, Dec 23 2013