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A109207
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Palindromic primes with digit sum = 50.
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2
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3998993, 7696967, 7778777, 7794977, 7868687, 7884887, 7958597, 9586859, 9758579, 9782879, 9938399, 138989831, 139969931, 148888841, 148969841, 157888751, 159929951, 166888661, 167787761, 168929861, 169666961, 174989471
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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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Do[p=Join[IntegerDigits[n], Reverse[Drop[IntegerDigits[n], -1]]]; q=Plus@@p; If[PrimeQ[FromDigits[p]]&&q==50, Print[FromDigits[p]]], {n, 1, 10^7}] (* Vincenzo Librandi, Dec 18 2015 *)
Select[Prime@ Range[10^7], And[# == Reverse@ #, Total@ # == 50] &@ IntegerDigits@ # &] (* Michael De Vlieger, Dec 18 2015 *)
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PROG
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(PARI) isok(n) = isprime(n) && (d=digits(n)) && (Vecrev(d)==d) && (sumdigits(n)==50); \\ Michel Marcus, Dec 18 2015
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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