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A063693
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Solutions to Phi[x+d[x]] = Phi[x]+d[x], where Phi[] = A000010(), d[] = A000005().
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1
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3, 5, 11, 17, 24, 29, 41, 42, 56, 59, 71, 98, 101, 102, 107, 137, 149, 179, 191, 197, 227, 230, 239, 248, 264, 269, 281, 294, 311, 347, 419, 431, 461, 468, 521, 569, 599, 617, 638, 641, 659, 809, 821, 827, 857, 881, 1014, 1016, 1019, 1031, 1049, 1061, 1078
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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LINKS
| Harry J. Smith, Table of n, a(n) for n=1,...,1000
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EXAMPLE
| Primes and composites among solutions: x = 59, d(58) = 2, Phi(59) = 58, Phi(59+2) = Phi(61) = 60 = Phi(59)+d(59); x = 56, d(56) = 8, Phi(56) = 24, Phi(56+8) = Phi(64) = 32 = Phi(56)+d(56).
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PROG
| (PARI) { n=0; for (x=1, 10^9, if (eulerphi(x + numdiv(x)) == (eulerphi(x) + numdiv(x)), write("b063693.txt", n++, " ", x); if (n==1000, break)) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 27 2009]
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CROSSREFS
| A000005, A000010.
Sequence in context: A158318 A099596 A200748 * A049752 A147350 A066692
Adjacent sequences: A063690 A063691 A063692 * A063694 A063695 A063696
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Aug 23 2001
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