OFFSET
1,2
COMMENTS
Nonprimes of the form A141468(k)//k, where double slashes represent concatenation, sorted along increasing k.
EXAMPLE
MAPLE
cat2 := proc(a, b) dgs := max(1, ilog10(b)+1) ; a*10^dgs+b ; end:
n := 0 ; for c from 0 to 80 do if not isprime(c) then n := n + 1 ; if not isprime(cat2(c, n)) then printf("%d, ", cat2(c, n)) ; fi; fi; od: # R. J. Mathar, Aug 03 2009
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Juri-Stepan Gerasimov, Jan 11 2009
EXTENSIONS
Edited by R. J. Mathar, Aug 03 2009
STATUS
approved