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A289364 Numbers n such that phi(x) = 12*n+2 is solvable, where phi is Euler's totient A000010. 1
0, 9, 42, 180, 285, 414, 567, 945, 1109, 1419, 2310, 2655, 3024, 4275, 4740, 5229, 5742, 8034, 10005, 10710, 12192, 14595, 15444, 16317, 18135, 19080, 20049, 21042, 22306, 26367, 28665, 29850, 34830, 36135, 38817, 43020, 45942, 56925, 58590, 61992, 65490 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The associated values in A002202 are 2, 110, 506, 2162, 3422,....

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..10000

J. B. Dence, T. P. Dence, A surprise regarding the equation phi(x)=2*(6*n+1), Coll. Math. J. 26 (4) (1995) 297-301.

FORMULA

{n: 12*n+2 in A002202}.

MATHEMATICA

phibnd[n_] := n/(Exp[EulerGamma] Log[Log[n]] + 3/Log[Log[n]]); up = 66000; m = 10^4; While[phibnd[m] <= 12 up + 2, m += 10^4]; Union@ Select[ (EulerPhi@ Range @ m - 2)/12, IntegerQ[#] && # <= up &] (* Giovanni Resta, Jul 04 2017 *)

CROSSREFS

Cf. A002202.

Sequence in context: A293101 A084899 A268622 * A074443 A221425 A007227

Adjacent sequences:  A289361 A289362 A289363 * A289365 A289366 A289367

KEYWORD

nonn

AUTHOR

R. J. Mathar, Jul 04 2017

EXTENSIONS

More terms from Giovanni Resta, Jul 04 2017

STATUS

approved

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Last modified May 20 12:33 EDT 2019. Contains 323422 sequences. (Running on oeis4.)