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A249951 Numbers n such that A113630(n) is prime.

%I A249951 #16 May 22 2025 10:21:41
%S A249951 3,5,8,23,42,62,63,75,90,98,177,192,207,213,222,228,233,263,288,297,
%T A249951 317,320,402,453,455,528,570,602,620,650,672,752,780,797,810,863,867,
%U A249951 870,875,912,932,935,978,1010,1043,1065,1067,1070,1110,1125,1133,1142,1190
%N A249951 Numbers n such that A113630(n) is prime.
%C A249951 A113630(n) = 1 + 2*n + 3*n^2 + 4*n^3 + 5*n^4 + 6*n^5 + 7*n^6 + 8*n^7 + 9*n^8.
%H A249951 Chai Wah Wu, <a href="/A249951/b249951.txt">Table of n, a(n) for n = 1..2434</a>
%e A249951 See example section of A113630.
%o A249951 (Python)
%o A249951 from sympy import isprime
%o A249951 A249951_list, m = [], [362880, -1229760, 1607760, -1011480, 309816, -40752, 1584, -4, 1]
%o A249951 for n in range(1,10**5+1):
%o A249951     for i in range(8):
%o A249951         m[i+1]+= m[i]
%o A249951     if isprime(m[-1]):
%o A249951         A249951_list.append(n)
%o A249951 (PARI) for(n=1,5000,s=sum(i=1,9,i*n^(i-1));if(ispseudoprime(s),print1(n,", "))) \\ _Derek Orr_, Nov 09 2014
%o A249951 (Magma) [n: n in [0..1500] | IsPrime(1+2*n+3*n^2+4*n^3+ 5*n^4+6*n^5+7*n^6+8*n^7+9*n^8)]; // _Vincenzo Librandi_, Nov 09 2014
%o A249951 (Haskell)
%o A249951 a249951 n = a249951_list !! (n-1)
%o A249951 a249951_list = filter ((== 1) . a010051'' . a113630) [1..]
%o A249951 -- _Reinhard Zumkeller_, Nov 22 2014
%Y A249951 Cf. A113630.
%Y A249951 Cf. A010051.
%K A249951 nonn
%O A249951 1,1
%A A249951 _Chai Wah Wu_, Nov 09 2014