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 A139101 Numbers that show the distribution of prime numbers up to the n-th prime minus 1, using "0" for primes and "1" for nonprime numbers. 10
 1, 10, 1001, 100101, 1001010111, 100101011101, 1001010111010111, 100101011101011101, 1001010111010111010111, 1001010111010111010111011111, 100101011101011101011101111101, 100101011101011101011101111101011111, 1001010111010111010111011111010111110111 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) has A000040(n)-1 digits, n-1 digits "0" and A000040(n)-n digits "1". LINKS MATHEMATICA Table[ sum = 0; For[i = 1, i <= Prime[n] - 1 , i++, sum = sum*2; If[! PrimeQ[i], sum++]]; IntegerString[sum, 2], {n, 1, 13}] (* Robert Price, Apr 03 2019 *) PROG (PARI) a(n) = fromdigits(vector(prime(n)-1, k, !isprime(k)), 10); \\ Michel Marcus, Apr 04 2019 CROSSREFS Binary representation of A139102. Subset of A118256. Cf. A000040, A018252, A139103, A139104, A139119, A139120, A139122. Sequence in context: A110147 A215023 A071925 * A015482 A288582 A104486 Adjacent sequences:  A139098 A139099 A139100 * A139102 A139103 A139104 KEYWORD nonn,base AUTHOR Omar E. Pol, Apr 08 2008 STATUS approved

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Last modified April 18 07:54 EDT 2021. Contains 343084 sequences. (Running on oeis4.)