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A261511
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Twin primes with both terms having distinct digits in descending order.
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0
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3, 5, 7, 41, 43, 71, 73, 641, 643, 76541, 76543, 87641, 87643
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OFFSET
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1,1
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COMMENTS
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Numbers in this list are the pairs of twin primes listed in A052014 with both terms having distinct digits in descending order
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LINKS
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MATHEMATICA
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dsc[n_] := 0 > Max@ Differences@ IntegerDigits@n; Union@ Flatten@ Select[ Partition[ Prime@ Range@ 9000, 2, 1], #[[2]] - #[[1]] == 2 && And @@ dsc /@ # &] (* Giovanni Resta, Aug 26 2015 *)
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PROG
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(PARI) lista(nn=100000) = {v = []; forprime(p=2, nn, if (isprime(p+2) && (d=digits(p)) && (vecsort(d, , 12)==d) && (dd=digits(p+2)) && (vecsort(dd, , 12)==dd), v = concat(v, p); v = concat(v, p+2)); ); vecsort(v, , 8); } \\ Michel Marcus, Aug 23 2015
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CROSSREFS
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KEYWORD
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nonn,easy,fini,full,base
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AUTHOR
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STATUS
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approved
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