OFFSET
1,1
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..1000
MATHEMATICA
fQ[n_] := ! PrimeQ@ n && Union@ Mod[ First /@ FactorInteger@ n, 10] == {1}; Rest@ Select[ Range@ 5950, fQ] (* Robert G. Wilson v, Mar 04 2012 *)
PROG
(Haskell)
a068872 n = a068872_list !! (n-1)
a068872_list = filter
(all (== 1) . map (`mod` 10) . a027750_row) a002808_list
-- Reinhard Zumkeller, Mar 08 2012
(PARI) is(n)=!isprime(n) && n>1 && vecmax(factor(n)[, 1]%10)==1 \\ Charles R Greathouse IV, Jun 19 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Mar 19 2002
EXTENSIONS
More terms from Sascha Kurz, Mar 23 2002
STATUS
approved