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A085345
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Least number x such that number of primes between phi(x) and x equals n.
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2
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2, 6, 12, 18, 24, 30, 50, 42, 48, 66, 60, 78, 96, 84, 90, 130, 108, 176, 114, 132, 156, 182, 150, 168, 186, 180, 216, 198, 228, 429, 210, 258, 308, 240, 276, 282, 270, 306, 294, 300, 354, 366, 336, 330, 384, 378, 396, 360, 432, 438, 622, 444, 390, 490, 474, 498
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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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N:= 200: # for a(1)..a(N)
V:= Vector(N):
count:= 0:
for x from 1 while count < N do
v:= numtheory:-pi(x) - numtheory:-pi(numtheory:-phi(x));
if v >= 1 and v <= N and V[v] = 0 then
V[v]:= x; count:= count+1;
fi
od:
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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