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A038211
Can express a(n) with the digits of a(n)^4 in order, only adding plus signs.
1
0, 1, 7, 10, 19, 22, 25, 27, 28, 34, 36, 37, 45, 52, 54, 55, 58, 61, 63, 64, 67, 72, 73, 76, 79, 81, 82, 85, 91, 100, 103, 106, 108, 109, 112, 115, 117, 118, 121, 124, 127, 133, 135, 142, 144, 145, 148, 153, 154, 157, 162, 163, 166, 169, 172, 175, 178, 180, 181
OFFSET
1,3
COMMENTS
All terms == 0, 1, 4 or 7 (mod 9). - Robert Israel, Sep 06 2020
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000 (first 5000 terms from Robert Israel)
EXAMPLE
a(6)=22 is in the sequence because 22^4=234256 and 2+3+4+2+5+6=22.
a(8)=27 is in the sequence because 27^4=531441 and 5+3+14+4+1=27.
MAPLE
F:= proc(n, t) local d; option remember;
if n = t then return true fi;
if n < t then return false fi;
for d from 1 to min(ilog10(t)+1, ilog10(n)+1) do
if procname(floor(n/10^d), t - (n mod 10^d)) then return true fi
od;
false
end proc:
select(t -> F(t^4, t), [$0..1000]); # Robert Israel, Sep 06 2020
CROSSREFS
KEYWORD
nonn,base
EXTENSIONS
Offset changed by Robert Israel, Sep 06 2020
STATUS
approved