A095092 - OEIS

A095092

Number of 4k+3 primes whose Legendre-vector is a Dyck-path (A095102) in range ]2^n,2^(n+1)].

1, 1, 1, 2, 2, 4, 7, 10, 16, 30, 51, 88, 153, 277, 509, 905, 1660, 3079, 5535, 10234, 19053

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OFFSET

1,4

LINKS

FORMULA

a(n) = A095008(n) - A095093(n).

PROG

(PARI) is(m) = {if(!isprime(m), return(0)); my(s=0); for(i=1, m-1, if((s+=kronecker(i, m))<0, return(0))); 1; }

a(n) = {my(c=0); forstep(m=2^n+3*(n>1), 2^(n+1), 4, c+=is(m)); c; } \\ Jinyuan Wang, Jul 20 2020

CROSSREFS

KEYWORD

nonn,more

AUTHOR

STATUS

approved