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A328804
The maximum value of j + k where j and k are positive integers with j^2 + k^2 = A001481(n).
1
0, 1, 2, 2, 3, 4, 3, 4, 5, 4, 5, 6, 6, 7, 6, 7, 8, 8, 6, 7, 8, 9, 9, 7, 10, 10, 9, 10, 11, 8, 11, 10, 12, 11, 12, 12, 9, 10, 13, 13, 12, 13, 14, 14, 11, 12, 14, 13, 15, 14, 15, 11, 12, 15, 16, 16, 16, 15, 12, 17, 16, 14, 17, 15, 17, 16, 18, 18, 17, 18, 15, 16
OFFSET
1,3
EXAMPLE
For n = 14, A001481(14) = 25 = 0^2 + 5^2 = 3^2 + 4^2, so a(14) = max{0+5, 3+4} = 7.
PROG
(Python)
from itertools import count, islice
from sympy.solvers.diophantine.diophantine import diop_DN
from sympy import factorint
def A328804_gen(): # generator of terms
return map(lambda n: max((a+b for a, b in diop_DN(-1, n))), filter(lambda n:(lambda m:all(d&3!=3 or m[d]&1==0 for d in m))(factorint(n)), count(0)))
A328804_list = list(islice(A328804_gen(), 30)) # Chai Wah Wu, Sep 09 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Kagey, Oct 27 2019
STATUS
approved