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Smallest odd prime p such that A258367(p) = n, or 0 if no such p exists.
1

%I #15 Jul 15 2015 02:26:38

%S 1093,3,17,11,59,13,571,1451,19,41,911,197,349,227,29,113,257,223,37,

%T 739,97,109,47,719,83,179,6619,3361,73,283,79,401,199,39929,229,277,

%U 17667847,281,29759,293,887,157,137,1709

%N Smallest odd prime p such that A258367(p) = n, or 0 if no such p exists.

%C Is a(n) > 0 for all n?

%o (PARI) a258367(n) = a=0; while(Mod(2, n^2)^((n-1)/2)!=1+a*n && Mod(2, n^2)^((n-1)/2)!=-1+a*n && Mod(2, n^2)^((n-1)/2)!=1-a*n && Mod(2, n^2)^((n-1)/2)!=-1-a*n, a++); a

%o for(n=0, 40, p=3; while(a258367(p)!=n, p=nextprime(p+1)); print1(p, ", "))

%Y Cf. A258367.

%K nonn,more

%O 0,1

%A _Felix Fröhlich_, May 28 2015

%E a(36)-a(43) from _Giovanni Resta_, Jun 15 2015