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A086884 Smallest string of 1's and 0's which is prime in every base from 2 to n. 1
10, 10, 101111, 10010111, 111110100001, 111110100001, 11000011101101111, 10011110011011110110110011, 110100000010101111110001010011001110001, 1000000010000011110100010001000101001010110111001 (list; graph; refs; listen; history; internal format)
OFFSET

2,1

LINKS

Phil Carmody, Bitstrings representing primes in many bases.

EXAMPLE

a(5) = 10010111 because 10010111 (base 2) = 151, 10010111 (base 3) = 2281, 10010111 (base 4) = 16661 and 10010111 (base 5) = 78781 are all prime and 10010111 is smallest such string.

MATHEMATICA

a[n_] := (While[b = FromDigits[ IntegerDigits[k, 2]]; Union[ PrimeQ[ Table[ FromDigits[ IntegerDigits[b], i], {i, 2, n}]]] != {True}, k++ ]; b); k = 1; Do[ Print[ a[n]], {n, 2, 10}]

CROSSREFS

See A086204 for decimal equivalents.

Sequence in context: A052983 A072804 A079793 * A176998 A173821 A101807

Adjacent sequences:  A086881 A086882 A086883 * A086885 A086886 A086887

KEYWORD

nonn

AUTHOR

Richard FitzHugh (fitzhughrichard(AT)hotmail.com), Aug 22 2003

EXTENSIONS

Edited by Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 24 2003

a(10) from Phil Carmody's Web site added by Dario A. Alpern (alpertron(AT)hotmail.com), May 14 2006

Cross-reference changed from A096204 to A086204 James G. Merickel (merk7(AT)verizon.net), Nov 18 2009

a(11) from Phil Carmody's website added by James G. Merickel (merk7(AT)verizon.net), Feb 15 2010

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.