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A064804 Numbers k such that phi(2*k + 2) < phi(2*k). 1
16, 22, 28, 34, 38, 40, 46, 52, 58, 64, 68, 76, 82, 86, 88, 94, 98, 100, 106, 112, 118, 124, 128, 130, 134, 136, 142, 148, 152, 154, 158, 160, 166, 172, 178, 184, 188, 190, 194, 196, 202, 206, 208, 214, 218, 220, 226, 232, 236, 238, 244, 248, 250, 256, 262, 268 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..1000

MATHEMATICA

2Select[ Range[200], EulerPhi[2# + 2] < EulerPhi[2# ] & ]

PROG

(PARI) { n=e=0; forstep (m=2, 10^9, 2, f=eulerphi(m); if (f<e, write("b064804.txt", n++, " ", m - 2); if (n==1000, return)); e=f ) } \\ Harry J. Smith, Sep 26 2009

CROSSREFS

Cf. A001837.

Sequence in context: A243972 A091118 A294125 * A102944 A058901 A059756

Adjacent sequences:  A064801 A064802 A064803 * A064805 A064806 A064807

KEYWORD

easy,nonn,changed

AUTHOR

Robert G. Wilson v, Oct 21 2001

EXTENSIONS

a(41)-a(56) from Harry J. Smith, Sep 26 2009

STATUS

approved

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Last modified June 19 13:11 EDT 2018. Contains 305595 sequences. (Running on oeis4.)