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A089294
Smallest prime p_k such that n can be written as a "plus-minus" sum n=sum_(i=1..k)e_i*(p_i)^2 with distinct primes p_i<=p_k, where e_i is 1 or -1.
3
19, 13, 19, 13, 2, 3, 13, 19, 13, 3, 13, 7, 5, 3, 13, 7, 5, 13, 13, 7, 5, 5, 13, 13, 7, 5, 13, 13, 7, 5, 5, 13, 13, 7, 5, 13, 7, 7, 5, 13, 7, 17, 11, 11, 7, 7, 17, 11, 13, 7, 17, 11, 11, 7, 7, 17, 11, 13, 7, 11, 11, 7, 7, 11, 13, 7, 17, 11, 11, 7, 7, 17, 11, 13, 7, 17, 11, 11, 7, 7, 17, 11
OFFSET
0,1
COMMENTS
The first terms where this sequence differs from A088934 are n=22,31,52,87,89,98,118,127,...
EXAMPLE
a(22)=13 because 22 can be represented as -13^2+11^2+7^2+5^2-2^2.
The corresponding representation with the minimum number of terms is
22=19^2-13^2-11^2-7^2 (A088934(22)=19, A088910(22)=4 terms)
CROSSREFS
The positions of the records in this sequence are given in A089295. Cf. A088910, A088934.
Sequence in context: A323832 A306384 A196188 * A088934 A177923 A155848
KEYWORD
nonn
AUTHOR
W. Edwin Clark Nov 06 2003
STATUS
approved