OFFSET
1,4
COMMENTS
Conjecture: The number of 1's in this sequence is infinite.
a(n) = 1 if and only if 2n is in A013916.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..200
EXAMPLE
n=1: 3x + 2, prime for x = 1, so a(1) = 1.
n=2: 7x^3 + 5x^2 + 3x + 2, prime for x = 1, so a(2) = 1.
n=3: 13x^5 + 11x^4 + 7x^3 + 5x^2 + 3x + 2, prime for x = 1, so a(3) = 1.
n=4: 19x^7 + 17x^6 + 13x^5 + 11x^4 + 7x^3 + 5x^2 + 3x + 2, prime for x = 11, so a(4) = 11.
PROG
(PARI) primenomial(n) = { ct=0; sr=0; p=0; d=0; d1=0; forstep(m=1, n, 2, for(x=0, n, y=2; for(j=2, m+1, p = prime(j); y+=x^(j-1)*p; );
if(y>2&&ispseudoprime(y), ct+=1; print1(x", "); break ); )) }
(PARI) a(n)=my(P=Polrev(primes(2*n)), k=1); while(!ispseudoprime(subst(P, 'x, k)), k+=2); k \\ Charles R Greathouse IV, Jan 15 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Cino Hilliard, Jan 31 2009
EXTENSIONS
a(39)-a(64) from Charles R Greathouse IV, Jan 17 2013
STATUS
approved