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A139103
Numbers that show the distribution of prime numbers up to the n-th prime using "0" for primes and "1" for nonprime numbers.
8
10, 100, 10010, 1001010, 10010101110, 1001010111010, 10010101110101110, 1001010111010111010, 10010101110101110101110, 10010101110101110101110111110, 1001010111010111010111011111010, 1001010111010111010111011111010111110, 10010101110101110101110111110101111101110
OFFSET
1,1
COMMENTS
a(n) has A000040(n) digits, n digits "0" and A000040(n)-n digits "1".
MATHEMATICA
Table[ sum = 0; For[i = 1, i <= Prime[n] , i++, sum = sum*2;
If[! PrimeQ[i], sum++]]; IntegerString[sum, 2], {n, 1, 20}] (* Robert Price, Apr 03 2019 *)
PROG
(PARI) a(n) = fromdigits(vector(prime(n), k, !isprime(k)), 10); \\ Michel Marcus, Apr 04 2019
CROSSREFS
Binary representation of A139104.
Subset of A118256.
Sequence in context: A173481 A135651 A220812 * A067217 A266175 A304237
KEYWORD
nonn,base
AUTHOR
Omar E. Pol, Apr 08 2008
EXTENSIONS
a(12)-a(13) from Robert Price, Apr 03 2019
STATUS
approved