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Primes in carryless arithmetic mod 10 in which all digits except the rightmost are zero or five.
5

%I #7 Mar 30 2012 17:38:11

%S 51,52,53,54,56,57,58,59,551,553,557,559,5051,5053,5057,5059,5501,

%T 5503,5507,5509,50051,50053,50057,50059,55001,55003,55007,55009,55551,

%U 55553,55557,55559,500501,500503,500507,500509,505001,505003

%N Primes in carryless arithmetic mod 10 in which all digits except the rightmost are zero or five.

%C These are called f-type primes.

%H <a href="/index/Ca#CARRYLESS">Index entries for sequences related to carryless arithmetic</a>

%Y A169887 = A163396 union A169984.

%K nonn,base

%O 1,1

%A _David Applegate_, _Marc LeBrun_ and _N. J. A. Sloane_, Aug 24 2010