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A196153 Primes of the form 2*n^3 + 5*n^2 + 3*n + 1. 0

%I #15 May 09 2018 10:40:14

%S 11,43,109,631,953,2531,3301,5279,9521,13339,15581,18061,38611,43093,

%T 70753,77419,99901,108263,180181,205391,218833,247451,262651,294893,

%U 329671,407219,472751,496063,520129,544961,652189,942943,1056241,1095931,1178269,1309351,1355113,1815841

%N Primes of the form 2*n^3 + 5*n^2 + 3*n + 1.

%C A rational number is created by 1/n + 1/n^2 + 1/(n+1) + 1/(n+1)^2 and has a reduced numerator of 2*n^3 + 5*n^2 + 3*n + 1.

%C From n=1 to 100, 38 primes, 48 semiprimes, and 14 numbers requiring three or more prime factors were created. This is very anomalous compared to the expected distribution of such numbers from 1 to 2050301.

%e For n=37, 2*37^3 + 5*37^2 + 3*37 + 1 = 108263, a prime.

%t Select[Table[2n^3+5n^2+3n+1,{n,100}],PrimeQ] (* _Harvey P. Dale_, Jan 21 2014 *)

%K nonn

%O 1,1

%A _J. M. Bergot_, Sep 28 2011

%E Entries corrected by _R. J. Mathar_, Sep 28 2011

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Last modified April 25 04:42 EDT 2024. Contains 371964 sequences. (Running on oeis4.)