

A047701


All positive numbers that are not the sum of 5 nonzero squares.


5



1, 2, 3, 4, 6, 7, 9, 10, 12, 15, 18, 33
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,2


REFERENCES

J.M. De Koninck, Ces nombres qui nous fascinent, Entry 33, pp 12, Ellipses, Paris 2008.
E. Grosswald, Representations of Integers as Sums of Squares. SpringerVerlag, NY, 1985, Theorem 2., p. 73.
Ivan Niven and Herbert S. Zuckerman, An Introduction to the Theory of Numbers, New York: John Wiley (1980), p. 145


LINKS

Table of n, a(n) for n=1..12.
Index entries for sequences related to sums of squares


EXAMPLE

4 = 1^2 + 1^2 + 1^2 + 1^2 + 0^2, but the last square is 0, and hence 4 is in the sequence.
5 = 1^2 + 1^2 + 1^2 + 1^2 + 1^2, and therefore 5 is not in the sequence.


MATHEMATICA

Select[ Range[100], Select[ PowersRepresentations[#, 5, 2], FreeQ[#, 0]& ] == {}& ] (* JeanFrançois Alcover, Sep 03 2013 *)


CROSSREFS

Cf. A047700, A000534, A180968 (not the sum of 6 squares).
Sequence in context: A246372 A006254 A111333 * A164528 A127963 A031403
Adjacent sequences: A047698 A047699 A047700 * A047702 A047703 A047704


KEYWORD

nonn,full,fini


AUTHOR

Arlin Anderson (starship1(AT)gmail.com)


EXTENSIONS

Name changed.  Wolfdieter Lang, Mar 28 2013


STATUS

approved



