A280447 - OEIS

%I #8 Jan 05 2017 05:49:38

%S 176594,281894,371894,446594,1765940,2818940,2822594,3718940,3722594,

%T 4465940,17659400,28189400,28225940,37189400,37225940,44659400

%N Like A065759 but where f(n) = 3*n.

%C Numbers of the form 176594*10^k, 281894*10^k, 371894*10^k, 446594*10^k, etc., with k>=0, belong to the sequence.

%e 176594 = concat(1,76594) = concat(17,6594) = concat(176,594) = concat(1765,94) = concat(17659,4) and (1*76594 + 17*6594 + 176*594 + 1765*94 + 17659*4) = 529782 = 3*176594.

%p P:=proc(q) local a,k,n; for n from 1 to q do a:=0;

%p for k from 1 to ilog10(n) do a:=a+(n mod 10^k)*trunc(n/10^k); od;

%p if a/n=3 then print(n); fi; od; end: P(10^9);

%Y Cf. A065759, A280445, A280446.

%K nonn,base,more

%O 1,1

%A _Paolo P. Lava_, Jan 03 2017