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A083571
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Numbers n such that A008509(n) is prime.
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3
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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palQ[n_]:=Reverse[x=IntegerDigits[n]]==x; t={}; c=0; Do[If[palQ[n*(n+1)/2], c=c+1; If[PrimeQ[n], AppendTo[t, c]]], {n, 10^3}]; t (* Jayanta Basu, May 14 2013 *)
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PROG
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(PARI) ispal(n)=n=digits(n); for(i=1, #n\2, if(n[i]!=n[#n+1-i], return(0))); 1
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CROSSREFS
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KEYWORD
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nonn,base,hard,more
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AUTHOR
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STATUS
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approved
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