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%I #6 Dec 15 2018 14:13:12
%S 103,312088729,9955641160957,163142317702973500798039087,
%T 327058383882861814163660125754017,
%U 67973813526967723994124686175157751059,545249446055539622797498212423248888694512551610580463
%N Primes of the form n*x^n + (n-1)*x^(n-1) + . . . + x + 1 for x=3.
%C Sum of reciprocals = 0.009708741068395080316898549713.. Are these primes infinite?
%C The next term (a(8)) has 148 digits. - _Harvey P. Dale_, Dec 15 2018
%e 3*3^3 + 2*3^2 + 3 + 1 = 103.
%t Select[Accumulate[Join[{1},Table[n*3^n,{n,200}]]],PrimeQ] (* _Harvey P. Dale_, Dec 15 2018 *)
%o (PARI) trajpolyp(n1,k) = { s=0; for(x1=0,n1, y1 = polypn2(k,x1); if(isprime(y1),print1(y1","); s+=1.0/y1; ) ); print(); print(s) } polypn2(n,p) = { x=n; y=1; for(m=0,p, y=y+m*x^m; ); return(y) }
%K nonn
%O 1,1
%A _Cino Hilliard_, Nov 20 2003
%E More terms from _Harvey P. Dale_, Dec 15 2018
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