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A087381 Let Compri(n) be the number obtained by replacing each prime digit (2,3,5,7) of n with a '1' and a composite digit( 0,4,6,8,9) with a '0'. A 1 remains the same. a(n) = Compri(n). 1
1, 1, 1, 0, 1, 0, 1, 0, 0, 10, 11, 11, 11, 10, 11, 10, 11, 10, 10, 10, 11, 11, 11, 10, 11, 10, 11, 10, 10, 10, 11, 11, 11, 10, 11, 10, 11, 10, 10, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 10, 11, 11, 11, 10, 11, 10, 11, 10, 10, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 10, 11, 11, 11, 10, 11, 10, 11, 10, 10, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,10

COMMENTS

For all numbers using only composite digits (0,4,6,8,9) a(n) = 0. For a 'k' digit number using 1 and/or only prime digits a(n) = (10^k-1)/9.

LINKS

Table of n, a(n) for n=1..80.

EXAMPLE

a(4206) = 100

a(10235479) = 10111010

CROSSREFS

Cf. A087380.

Sequence in context: A077812 A004288 A065016 * A136400 A121266 A045988

Adjacent sequences:  A087378 A087379 A087380 * A087382 A087383 A087384

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Sep 09 2003

EXTENSIONS

More terms from David Wasserman, May 25 2005

STATUS

approved

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Last modified October 20 20:24 EDT 2019. Contains 328273 sequences. (Running on oeis4.)