OFFSET
1,2
COMMENTS
a(p) = p. Conjecture; There are infinitely many composite numbers n such that a(n) is nonzero.
EXAMPLE
a(10) = 109 a concatenation of 10 and 9.
a(6) = 0 as no number in the sequence 6,65,654,6543,65432,654321 is prime.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Sep 16 2003
EXTENSIONS
Corrected and extended by Gabriel Cunningham (gcasey(AT)mit.edu), Sep 21 2003
STATUS
approved