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A089689 a={1,3,7,9} a1={0,1,3,7,9} b[n]=Flatten[Table[10*Sum[10^m*a1[[1+Mod[n+m,5]]],{m,0,n}]+a,{n,0,digits}]] a(m) = If b[n] is prime then b[n] 0
3, 7, 311, 313, 317, 9733, 9739, 10973, 10979, 31097317, 73109731091, 97310973101, 97310973103, 97310973109733, 7310973109731091, 73109731097310973109731097, 97310973109731097310973101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A sum method for producing a prime set based of two digits sets.

LINKS

Table of n, a(n) for n=1..17.

MATHEMATICA

a={1, 3, 7, 9} a1={0, 1, 3, 7, 9} digits=100 b=Flatten[Table[10*Sum[10^m*a1[[1+Mod[n+m, 5]]], {m, 0, n}]+a, {n, 0, digits}]]; c=Table[If[PrimeQ[b[[n]]]==True, b[[n]], 0], {n, 1, Dimensions[b][[1]]}] d=Delete[Union[c], 1]

CROSSREFS

Sequence in context: A088097 A064774 A348376 * A248701 A103317 A104051

Adjacent sequences:  A089686 A089687 A089688 * A089690 A089691 A089692

KEYWORD

nonn,base,less,uned

AUTHOR

Roger L. Bagula, Jan 05 2004

STATUS

approved

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Last modified May 26 04:26 EDT 2022. Contains 354074 sequences. (Running on oeis4.)