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A088194
Members of the difference sequence (A088191) of the sequence of largest quadratic residues modulo the primes (A088190), where the latter is non-monotonic.
6
0, 0, 0, -1, 0, 0, 0, 0, 0, -5, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, -10, -1, 0, 0, 0, 0, 0, 0, -7, 0, -4, 0, -1, 0, -5, 0, 0, 0, 0, 0, -7, 0, -4, 0, 0, 0, 0, 0, -4, 0, 0, -2, 0, -1, 0, -5, 0, 0, 0, 0, -8, 0, 0, 0, 0, -4, -11, 0, 0, 0, -1, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, -5, 0, 0, 0, 0, -5, 0, 0, -5, 0, 0, 0, -1
OFFSET
1,10
COMMENTS
The negative values are either primes or composites (Cf. A088200).
PROG
(PARI) qrp_d_nm(to)= {/* The difference sequence values where the sequence of the largest QR modulo the primes is non-monotonic */ local(m, k=1, p, v=[]); for(i=2, to, m=1; p=prime(i); j=2; while((j<=(p-1)/2)&&(m<p-1), m=max(m, (j^2)%p); j++); if((m-k)<=0, v=concat(v, m-k)); k=m); print(v) }
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Ferenc Adorjan (fadorjan(AT)freemail.hu), Sep 22 2003
STATUS
approved