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A063069
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Positive integers n such that phi(n) - d(n) = phi(n+1) - d(n+1) where d(n) is the number of divisors of n.
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1
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45, 104, 345, 3255, 17534, 22935, 70634, 983775, 1025504, 1156701, 2200694, 2619705, 2745765, 4163355, 4447064, 4695704, 6372794, 9718904, 11903775, 23992215, 26879684, 29357475, 37239735, 40588485, 41207144, 42694197, 48615735, 56424555, 76466985
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OFFSET
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1,1
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LINKS
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PROG
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(PARI) for(n=1, 10^5, if(eulerphi(n)-numdiv(n)==eulerphi(n+1)-numdiv(n+1), print(n)))
(PARI) { n=0; s=1; for (m=1, 10^9, if (s!=(r=(eulerphi(m) - numdiv(m))), s=r, write("b063069.txt", n++, " ", m - 1); if (n==100, break)) ) } \\ Harry J. Smith, Aug 16 2009
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CROSSREFS
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KEYWORD
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hard,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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