OFFSET
0,2
COMMENTS
It appears that a(n) does not exist for n in {12, 24, 39, 40, 48, 50, 53, 58, 60, 64, 67, 70, 71, 75, 78, 81, 83, 85, 86, 87, 91, 92, 96, 102, 103, 108, 113, 115, 120, 122, 123, 124, 128, 129, 130, 132, 135, 136, 138, 140, 142, 143, 144, 145, 148, 150, 151, 155, 156, 158, 160, 161, 164, 168, 170, 171, 172, 174, 175, 177, 178, 181, 183, 185, 186, 188, 189, 190, 196, 197, 198, 199, 200}; i.e., there is no integer whose number of representations is any of these values.
REFERENCES
E. Grosswald, Representations of Integers as Sums of Squares. Springer-Verlag, New York, 1985, p. 86, Theorem 1.
LINKS
D. H. Lehmer, On the Partition of Numbers into Squares, The American Mathematical Monthly, Vol. 55, No. 8, October 1948, pp. 476-481.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert Price, Nov 29 2017
STATUS
approved