OFFSET
1,2
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = n + O(n^(3/4)). - Charles R Greathouse IV, Sep 01 2015
EXAMPLE
3 cannot be represented as a^4 + b^2 and thus is in this sequence while 10 = 1^4 + 3^2 is not.
PROG
(PARI) list(lim)=lim\=1; my(v=List(), u=vectorsmall(lim), m2); for(m=1, sqrtint(lim-1), m2=m^2; for(n=1, sqrtnint(lim-m2, 4), u[m2+n^4]=1)); for(i=1, #u, if(!u[i], listput(v, i))); Set(v) \\ Charles R Greathouse IV, Sep 01 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Stefan Steinerberger, Nov 25 2005
STATUS
approved