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A167412
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Primes p such that sum of (digits^2) + 1 is prime.
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2
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2, 11, 13, 19, 31, 37, 59, 73, 79, 97, 101, 103, 109, 163, 181, 211, 233, 251, 257, 277, 307, 349, 383, 439, 499, 509, 521, 541, 563, 587, 613, 631, 653, 709, 727, 769, 787, 811, 857, 877, 907, 929, 967, 1009, 1021, 1063, 1117, 1151, 1153, 1171, 1201, 1223
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OFFSET
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1,1
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COMMENTS
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11 is a term because 1^2 + 1^2 + 1 = 3 (prime);
163 is a term because 1^2 + 6^2 + 3^2 + 1 = 47;
277 is a term because 2^2 + 7^2 + 7^2 + 1 = 103.
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LINKS
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MAPLE
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A003132 := proc(n) local d; add(d^2, d=convert(n, base, 10)) ; end proc: A167412 := proc(n) local p; if n = 1 then 2; else p := nextprime(procname(n-1)) ; while not isprime(A003132(p)+1) do p := nextprime(p) ; end do ; return p end if ; end proc: seq(A167412(n), n=1..80) ; # R. J. Mathar, Nov 04 2009
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MATHEMATICA
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Select[Prime[Range[2000]], PrimeQ[Total[IntegerDigits[#]^2] + 1]&] (* Vincenzo Librandi, Sep 25 2014 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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2, 211, 233 inserted and more terms after 653 added by R. J. Mathar, Nov 04 2009
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STATUS
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approved
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