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Blue-code restricted to irreducible polynomials over GF(2): a(n) = A193231(A014580(n)).
4

%I #17 Apr 29 2021 04:10:27

%S 3,2,7,13,11,19,31,25,55,61,59,37,47,41,87,91,67,73,103,97,109,117,

%T 115,253,241,247,239,229,203,193,211,213,171,167,185,191,157,145,137,

%U 143,131,285,283,319,313,301,299,351,333,357,355,361,375,369,379,505,499,501

%N Blue-code restricted to irreducible polynomials over GF(2): a(n) = A193231(A014580(n)).

%C The polynomials are encoded as the number whose binary representation is given by the coefficients of the polynomial, e.g., 13 = 2^3 + 2^2 + 2^0 = 1101_2 encodes 1*X^3 + 1*X^2 + 0*X^1 + 1*X^0 = X^3 + X^2 + 1. - _Peter Munn_, Apr 28 2021

%H Antti Karttunen, <a href="/A234750/b234750.txt">Table of n, a(n) for n = 1..2538</a>

%H <a href="/index/Ge#GF2X">Index entries for sequences operating on (or containing) GF(2)[X]-polynomials</a>

%F a(n) = A193231(A014580(n)).

%e From _Peter Munn_, Apr 23 2021: (Start)

%e Table for polynomials of degree less than 6:

%e n A014580 a(n) Previous 2 columns

%e (n) in binary

%e 1 2 3 10 11

%e 2 3 2 11 10

%e 3 7 7 111 111

%e 4 11 13 1011 1101

%e 5 13 11 1101 1011

%e 6 19 19 10011 10011

%e 7 25 31 11001 11111

%e 8 31 25 11111 11001

%e 9 37 55 100101 110111

%e 10 41 61 101001 111101

%e 11 47 59 101111 111011

%e 12 55 37 110111 100101

%e 13 59 47 111011 101111

%e 14 61 41 111101 101001

%e (End)

%o (Scheme) (define (A234750 n) (A193231 (A014580 n)))

%Y Cf. A234751, A193231, A014580.

%K nonn,base

%O 1,1

%A _Antti Karttunen_, Feb 12 2014