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A140891 Binary encoding of the prime-ness of the 6 integers r+14*n with remainder r=1, 3, 5, 9, 11 or 13. 0
9, 49, 20, 42, 41, 20, 27, 33, 62, 10, 39, 21, 11, 39, 60, 30, 49, 28, 43, 41, 28, 31, 49, 55, 14, 53, 53, 42, 51, 29, 14, 51, 22, 58, 45, 22, 59, 57, 55, 46, 37, 29, 11, 43, 60, 14, 53, 60, 42, 59, 54, 27, 43, 54, 26, 61, 29, 15, 39, 28, 31, 49, 23, 58, 47, 54, 27, 53, 62, 42 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
Classify all integers 14n+r with r= 1, 3, 5, 9, 11 or 13 as nonprime or prime and assign hit positions 0=LSB, 1, 2, 3, 4, 5=MSB to the 6 remainders in the same order. Raise the bit if 14n+r is nonprime, erase it if 14n+r is prime.
The sequence interprets this as a number in base 2 and shows the decimal representation.
LINKS
EXAMPLE
For n=2, the 6 numbers 29 (r=1), 31 (r=3), 33 (r=5), 37 (r=9), 39 (r=11) and 41 (r=13) are prime, prime, nonprime, prime, nonprime, prime, which is rendered into the binary 001010 = 2^2+2^4=4+16=20=a(2).
MATHEMATICA
f[n_]:=FromDigits[1-Boole[PrimeQ[({13, 11, 9, 5, 3, 1}+14n)]], 2]; Table[f[n], {n, 0, 100}] (* Ray Chandler, Feb 20 2009 *)
CROSSREFS
Sequence in context: A293095 A283092 A249780 * A072461 A181607 A012260
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected and extended by Ray Chandler, Feb 20 2009
STATUS
approved

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Last modified May 8 19:26 EDT 2024. Contains 372341 sequences. (Running on oeis4.)