%I #27 Aug 28 2020 03:14:23
%S 1,4,6,17,28,39,50,61,72,83,94,109,120,131,142,153,164,175,186,197,
%T 199,210,221,232,243,254,265,276,287,298,300,311,322,333,344,355,366,
%U 377,388,399,401,412,423,434,445,456,467,478,489,500,502,513,524,535,546,557
%N Indices m of repunits R_m that are Colombian (or self) numbers.
%H David A. Corneth, <a href="/A337208/b337208.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) upto(n)= {my(res = List()); for(i = 1, n, if(is(i), listput(res, i); print1(i", "))); res}
%o is(n) = {c = 10^n \ 9; is_A003052(c)}
%o is_A003052(n)={for(i=1, min(n\2, 9*#digits(n)), sumdigits(n-i)==i && return); n} \\ from _M. F. Hasler_, Mar 20 2011
%Y Cf. A002275 (repunits), A003052 (Colombian (or self)), A004022 (repunit primes), A004023 (indices of repunit primes), complement of A337139.
%K nonn,base
%O 1,2
%A _David A. Corneth_, Aug 19 2020