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 A187559 Primes arising in A187234. 1
 2, 3, 5, 7, 2, 3, 5, 7, 2, 3, 5, 7, 3, 5, 7, 11, 13, 17, 19, 2, 5, 11, 17, 23, 29, 3, 7, 11, 19, 23, 31, 19, 29, 5, 11, 17, 23, 29, 41, 47, 53, 59, 13, 41, 7, 23, 31, 47, 71, 79, 17, 53, 71, 89, 19, 29, 59, 79, 89, 2, 2, 5, 11, 17, 23, 29, 11, 31, 41, 17, 31, 59, 73, 23, 41, 59, 29, 73, 3, 3, 7, 11, 19, 23, 31, 11, 31, 41, 19, 47, 61, 23 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(22) = 11 because A187234(22) = 123, and 1*2 + 1*3 + 2*3 = 11 is prime. MAPLE with(numtheory):T:=array(1..10):k:=1:for n from 1 to 1000 do:l:=length(n):n0:=n:for   m from 1 to l do:q:=n0:u:=irem(q, 10):v:=iquo(q, 10):n0:=v :T[m]:=u:od: s:=0:   for i from 1 to l-1 do: for j from i+1 to l do: s:=s+T[i]*T[j]:od: od:if type(s, prime)   = true then printf(`%d, `, s):else fi:od: CROSSREFS Cf. A187234. Sequence in context: A032759 A142711 A093338 * A104212 A139751 A076779 Adjacent sequences:  A187556 A187557 A187558 * A187560 A187561 A187562 KEYWORD nonn,base,easy AUTHOR Michel Lagneau, Mar 11 2011 STATUS approved

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