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A280729
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(p-1)/2 + phi(p-1) as p runs through the odd primes.
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1
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2, 4, 5, 9, 10, 16, 15, 21, 26, 23, 30, 36, 33, 45, 50, 57, 46, 53, 59, 60, 63, 81, 84, 80, 90, 83, 105, 90, 104, 99, 113, 132, 113, 146, 115, 126, 135, 165, 170, 177, 138, 167, 160, 182, 159, 153, 183, 225, 186, 228, 215, 184, 225, 256, 261, 266, 207, 226, 236, 233
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OFFSET
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1,1
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LINKS
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FORMULA
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MAPLE
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local p;
p := ithprime(n+1) ;
(p-1)/2+numtheory[phi](p-1) ;
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MATHEMATICA
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Table[(n - 1)/2 + EulerPhi[n - 1], {n, Prime[Range[2, 100]]}]
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PROG
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(Magma) [(NthPrime(n)-1)/2+EulerPhi(NthPrime(n)-1): n in [2..100]];
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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