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A160751
a(n) is the smallest n-digit prime formed by appending a digit to a(n-1); a(1)=6.
3
6, 61, 613, 6131
OFFSET
1,1
COMMENTS
There is no prime a(5) since all the integers from 61310 to 61319 are composite.
MAPLE
A160751 := proc(n) option remember ; local d; if n =1 then 6; else for d from 1 to 9 by 2 do if isprime(10*procname(n-1)+d) then RETURN( 10*procname(n-1)+d ) ; fi; od: RETURN(-1) ; fi; end: seq(A160751(n), n=1..10) ; # R. J. Mathar, May 26 2009
CROSSREFS
Sequence in context: A155458 A152281 A053462 * A236670 A142970 A034659
KEYWORD
base,easy,fini,full,nonn
AUTHOR
EXTENSIONS
Corrected by R. J. Mathar, May 26 2009
STATUS
approved