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%I #19 Apr 29 2016 05:13:27
%S 1,4,9,29,100,317,1007,3146,10016,31712,100204,316799,1002314,3169309,
%T 10022310,31693094
%N Total number of n-digit numbers requiring 2 positive biquadrates in their representation as sum of biquadrates.
%C A102831(n) + a(n) + A186652(n) + A186654(n) + A186656(n) + A186658(n) + A186660(n) + A186662(n) + A186664(n) + A186666(n) + A186668(n) + A186670(n) + A186672(n) + A186674(n) + A186676(n) + A186678(n) + A186681(n) + A186683(n) + A186685(n) = A052268(n), for n>1.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/WaringsProblem.html">Waring's Problem.</a>
%F a(n) = A186649(n)-A186649(n-1).
%p isbiquadrate:=proc(n) type(root(n,4),posint); end:
%p isA003336:=proc(n) local x,y4; if isbiquadrate(n) then false; else for x from 1 do y4:=n-x^4; if y4<x^4 then return false; elif isbiquadrate(y4) then return true; fi; od; fi; end:
%p a:=proc(n) local i,k; i:=0; for k from 10^(n-1) to 10^n-1 do if isA003336(k) then i:=i+1; fi; od: return(i); end: for n from 1 do print(a(n)); od;
%Y Cf. A003336, A186649.
%K nonn,base,more
%O 1,2
%A _Martin Renner_, Feb 25 2011
%E a(6) from _Martin Renner_, Feb 26 2011
%E a(7)-a(16) from _Giovanni Resta_, Apr 29 2016
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