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A038211 Can express a(n) with the digits of a(n)^4 in order, only adding plus signs.

%I A038211 #14 Sep 07 2020 13:50:46
%S A038211 0,1,7,10,19,22,25,27,28,34,36,37,45,52,54,55,58,61,63,64,67,72,73,76,
%T A038211 79,81,82,85,91,100,103,106,108,109,112,115,117,118,121,124,127,133,
%U A038211 135,142,144,145,148,153,154,157,162,163,166,169,172,175,178,180,181
%N A038211 Can express a(n) with the digits of a(n)^4 in order, only adding plus signs.
%C A038211 All terms == 0, 1, 4 or 7 (mod 9). - _Robert Israel_, Sep 06 2020
%H A038211 David A. Corneth, <a href="/A038211/b038211.txt">Table of n, a(n) for n = 1..10000</a> (first 5000 terms from Robert Israel)
%e A038211 a(6)=22 is in the sequence because 22^4=234256 and 2+3+4+2+5+6=22.
%e A038211 a(8)=27 is in the sequence because 27^4=531441 and 5+3+14+4+1=27.
%p A038211 F:= proc(n,t) local d; option remember;
%p A038211    if n = t then return true fi;
%p A038211    if n < t then return false fi;
%p A038211    for d from 1 to min(ilog10(t)+1,ilog10(n)+1) do
%p A038211      if procname(floor(n/10^d), t - (n mod 10^d)) then return true fi
%p A038211    od;
%p A038211    false
%p A038211 end proc:
%p A038211 select(t -> F(t^4,t), [$0..1000]); # _Robert Israel_, Sep 06 2020
%Y A038211 Cf. A001477, A038206, A038209.
%K A038211 nonn,base
%O A038211 1,3
%A A038211 _Erich Friedman_
%E A038211 Offset changed by _Robert Israel_, Sep 06 2020