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A105991 Semiprimes consisting of digit 0 and 1 only. 0
10, 111, 1011, 1101, 1111, 11101, 11111, 110111, 111011, 111101, 1111111, 11011111, 11111011, 110111111, 111011111, 111110111, 11101111111, 11111111111, 110111111111, 111101111111, 111111101111, 111111111011 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

This includes repunit semiprimes also.

EXAMPLE

a(3)=1011 is a term because 1011 is a semiprime and contain digits 0 and 1 only.

CROSSREFS

Sequence in context: A100751 A004290 A159551 * A103581 A087545 A078252

Adjacent sequences:  A105988 A105989 A105990 * A105992 A105993 A105994

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta (guptass(AT)rediffmail.com), Apr 29 2005

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Last modified February 14 10:24 EST 2012. Contains 205614 sequences.