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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A175801 Number of real zeros of the polynomial whose coefficients are the decimal digits of prime(n).

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%I A175801 #12 May 12 2019 02:23:00
%S A175801 0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,2,0,0,
%T A175801 0,2,0,2,2,2,2,2,2,2,2,2,0,0,0,0,0,0,2,2,0,2,0,2,0,2,2,2,0,0,0,0,0,0,
%U A175801 0,0,0,0,0,2,0,2,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,2,0,0
%N A175801 Number of real zeros of the polynomial whose coefficients are the decimal digits of prime(n).
%C A175801 a(n) is the number of real zeros of the polynomial Sum_{k>=0} d(k) x^k
%C A175801   where d(k) are the digits of the decimal expansion of prime(n) = Sum_{k>=0} 10^k*d(k).
%e A175801 a(167) = 2 because prime(167) = 991 => P(167,x) = 1 + 9*x + 9*x^2 has 2 real-valued roots, -0.8726779962... and -0.1273220038...
%p A175801 A175801 := proc(n) d := convert(ithprime(n),base,10) ; P := add( op(i,d)*x^(i-1),i=1..nops(d)) ; [fsolve(P,x,real)] ; nops(%) ; end proc:
%p A175801 seq(A175801(n),n=1..45) ; # _R. J. Mathar_, Dec 06 2010
%Y A175801 Cf. A173667.
%K A175801 nonn,base
%O A175801 1,32
%A A175801 _Michel Lagneau_, Dec 04 2010