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A089685 a={1,3,7,9} p[n]=Prime[n]*10+a[[1+Mod[n,4]]] a(m) = if p[n] is prime, then p[n] 0

%I

%S 23,37,59,71,113,137,179,191,233,479,593,617,733,797,839,1039,1093,

%T 1279,1373,1499,1511,1637,1931,1973,1997,2273,2297,2339,2579,2693,

%U 2833,3079,3319,3371,3539,3673,4019,4091,4217,4637,4679,4999,5639,5879,6079,6131

%N a={1,3,7,9} p[n]=Prime[n]*10+a[[1+Mod[n,4]]] a(m) = if p[n] is prime, then p[n]

%C A prime generator function based on the primes and the digit set {1,3,7,9}.

%t a={1, 3, 7, 9} digits=3*200 b=Table[Prime[n]*10+a[[1+Mod[n, 4]]], {n, 1, digits}] c=Table[If[PrimeQ[b[[n]]]==True, b[[n]], 0], {n, 1, digits}] d=Delete[Union[c], 1]

%K nonn

%O 1,1

%A _Roger L. Bagula_, Jan 05 2004

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Last modified June 29 20:54 EDT 2022. Contains 354913 sequences. (Running on oeis4.)