%I A001494 M3293 N1328
%S A001494 4,7,8,10,26,32,70,74,122,146,308,314,386,512,554,572,626,635,728,794,
%T A001494 842,910,914,1015,1082,1226,1322,1330,1346,1466,1514,1608,1754,1994,
%U A001494 2132,2170,2186,2306,2402,2426,2474,2590,2642,2695,2762,2906,3242,3314
%N A001494 Numbers n such that phi(n) = phi(n+2).
%C A001494 If p and 2p-1 are odd primes then 2(2p-1) is a solution of the equation.
Other terms (7,8,32,70,...) are not of this form.
%D A001494 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences,
Academic Press, 1995 (includes this sequence).
%D A001494 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973
(includes this sequence).
%D A001494 V. L. Klee, Jr., Some remarks on Euler's totient function, Amer. Math.
Monthly, 54 (1947), 332.
%D A001494 L. Moser, Some equations involving Euler's totient function, Amer. Math.
Monthly, 56 (1949), 22-23.
%D A001494 R. K. Guy, Unsolved Problems Number Theory, Sect. B36.
%D A001494 D. M. Burton, Elementry Number Theory, section 7-2.
%H A001494 T. D. Noe, <a href="b001494.txt">Table of n, a(n) for n=1..1000</a>
%Y A001494 Cf. A000010, A001274.
%Y A001494 Sequence in context: A026316 A091158 A084791 this_sequence A092214 A128373
A080578
%Y A001494 Adjacent sequences: A001491 A001492 A001493 this_sequence A001495 A001496
A001497
%K A001494 nonn,nice
%O A001494 1,1
%A A001494 N. J. A. Sloane (njas(AT)research.att.com).
%E A001494 More terms from Jud McCranie (j.mccranie(AT)comcast.net), Dec 24 1999
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