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A140387 Binary encoding of the location of primes in integer sets r+30*n with remainder r=1,7,11,..,29. 1

%I

%S 1,32,16,129,73,36,194,6,42,176,225,12,21,89,18,97,25,243,44,44,196,

%T 34,166,90,149,152,109,66,135,225,89,169,169,28,82,210,33,213,179,170,

%U 38,92,15,96,252,171,94,7,209,2,187,22,153,9,236,197,71,179,212,197,186

%N Binary encoding of the location of primes in integer sets r+30*n with remainder r=1,7,11,..,29.

%C Classify all integers 30n+r with r= 1, 7, 11, 13, 17, 19, 23 or 29 as nonprime or prime and assign bit positions 0=LSB, 1, 2, 3, .., 7=MSB to the 8 remainders in the same order. Raise the bit if 30n+r is nonprime, erase it if 30n+r is prime.

%C The sequence interprets this as a number in base 2 and shows the decimal representation.

%e For n=1, the 8 numbers 31 (r=1), 37 (r=7), 41 (r=11), 43 (r=17), 47 (r=17), 49 (r=19), 53 (r=23) and 59 (r=29) are prime, prime, prime, prime, prime, nonprime, prime, prime, prime, which is rendered into the binary 000100000 = 2^5=32=a(1).

%Y Cf. A132236, A132235, A132234, A039919, A132233, A132232, A136066, A140378.

%K nonn,less

%O 1,2

%A _Juri-Stepan Gerasimov_, Jun 10 2008

%E Edited by R. J. Mathar, Jun 17 2008

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Last modified August 18 20:02 EDT 2019. Contains 326109 sequences. (Running on oeis4.)