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4k+3 primes whose Legendre-vector is not valid Dyck-path.
6

%I #25 Jan 11 2022 12:42:17

%S 19,43,67,107,127,139,163,179,211,223,227,283,307,331,347,367,379,443,

%T 463,467,487,491,499,523,547,571,587,619,631,643,683,691,727,739,787,

%U 811,823,827,859,883,907,947,967,1019,1051,1087,1123,1163

%N 4k+3 primes whose Legendre-vector is not valid Dyck-path.

%H A. Karttunen and J. Moyer, <a href="/A095062/a095062.c.txt">C-program for computing the initial terms of this sequence</a>

%F a(n) = 4*A095273(n) + 3.

%t L = {}; Do[p = Prime[k]; If[Mod[p, 4] == 3 && Min[Table[Sum[JacobiSymbol[n, p], {n, 0, m}], {m, 0, p - 1}]] < 0, L = Append[L, p]], {k, 1, 192}]; L (* From Jonathan Sondow, Oct 25 2011 *)

%o (PARI) isok(m) = {my(s=0); if(m%4==3&&isprime(m), for(i=1, m-1, if((s+=kronecker(i, m))<0, return(1)))); 0; } \\ _Jinyuan Wang_, Jul 20 2020

%o (Sage)

%o def A095103_list(n) :

%o def is_Motzkin(n, k):

%o s = 0

%o for i in (1..k) :

%o s += jacobi_symbol(i, n)

%o if s < 0 : return false

%o return true

%o P = filter(is_prime, range(n+1)[3::4])

%o return filter(lambda m: not is_Motzkin(m, m//2), P)

%o A095103_list(1163) # _Peter Luschny_, Aug 08 2012

%Y Intersection of A000040 and A095101. Complement of A095102 in A002145.

%Y Cf. A095093, A095108 (diving indices).

%K nonn

%O 1,1

%A _Antti Karttunen_, Jun 01 2004