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A225741
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Primes p such that the sum of the squares of the digits of p plus p is the square of a prime.
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1
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71, 1997, 2707, 3407, 32647, 143509, 177131, 196073, 273433, 292517, 360977, 418447, 477341, 578789, 981769, 1066867, 1079269, 1125559, 1394539, 2024831, 2246851, 2679493, 3659401, 3736351, 4932637, 5148233, 5479939, 5726257, 5726321, 5755051, 7070093, 7091339, 7789289, 8082419
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OFFSET
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1,1
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LINKS
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EXAMPLE
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71 is a member since 71+(7^2+1^2)=11^2, 1997 is a member since 1997+(1^2+9^2+9^2+7^2)= 47^2.
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PROG
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(PARI) ssd(n)=my(d=digits(n)); sum(i=1, #d, d[i]^2)
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CROSSREFS
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KEYWORD
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nonn,base,less
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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