OFFSET
1,1
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..10000
EXAMPLE
a(1) = 3 = 1^4 + 1^3 + 1^2.
a(2) = 6 = 1^4 + 1^3 + 2^2.
a(3) = 10 = 1^4 + 2^3 + 1^2.
a(4) = 11 = 1^4 + 1^3 + 3^2.
a(5) = 13 = 1^4 + 2^3 + 2^2.
a(6) = 18 = 1^4 + 1^3 + 4^2 = 1^4 + 2^3 + 3^2 = 2^4 + 1^3 + 1^2.
MAPLE
isA123053 := proc(n)
local x, y, z ;
for x from 1 do
if x^2 > n then
return false;
end if;
for y from 1 do
if x^2+y^3> n then
break;
end if;
for z from 1 do
if x^2+y^3+z^4 > n then
break;
elif x^2+y^3+z^4 = n then
return true;
end if;
end do:
end do:
end do:
end proc:
n := 1 ;
for c from 0 to 10000 do
if isA123053(c) then
printf("%d %d\n", n, c) ;
n := n+1 ;
end if;
end do: # R. J. Mathar, Sep 07 2020
MATHEMATICA
Select[ Union[ Total /@ Tuples[{Range[64]^2, Range[8]^4, Range[16]^3}]], # < 200 &] (* Giovanni Resta, Jun 12 2016 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Sep 25 2006
EXTENSIONS
38, 86, and 93 added and 108 deleted by Giovanni Resta, Jun 12 2016
STATUS
approved