cp's OEIS Frontend

A038209 Can express a(n) with the digits of a(n)^3 in order, only adding plus signs.

%I A038209 #14 Sep 08 2020 03:00:29
%S A038209 0,1,8,10,17,18,26,27,28,45,55,62,63,71,72,81,82,89,91,99,100,107,108,
%T A038209 109,116,125,134,136,143,144,145,153,154,161,181,188,189,197,198,199,
%U A038209 206,207,208,215,216,224,226,233,234,235,242,243,244,253,261,262,269
%N A038209 Can express a(n) with the digits of a(n)^3 in order, only adding plus signs.
%C A038209 All terms == 0, 1 or 8 (mod 9). - _Robert Israel_, Sep 07 2020
%H A038209 Robert Israel, <a href="/A038209/b038209.txt">Table of n, a(n) for n = 1..5500</a>
%e A038209 62^3 = 238328 and 23+8+3+28 = 62.
%p A038209 F:= proc(n, t) local d; option remember;
%p A038209    if n = t then return true fi;
%p A038209    if n < t then return false fi;
%p A038209    for d from 1 to min(ilog10(t)+1, ilog10(n)+1) do
%p A038209      if procname(floor(n/10^d), t - (n mod 10^d)) then return true fi
%p A038209    od;
%p A038209    false
%p A038209 end proc:
%p A038209 A:=select(t -> F(t^3, t), [$0..1000]); # _Robert Israel_, Sep 07 2020
%K A038209 nonn,base
%O A038209 1,3
%A A038209 _Erich Friedman_
%E A038209 Offset changed by _Robert Israel_, Sep 07 2020