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A279106 a(n) = number of legs in each part of the symmetric representation of sigma(A279105(n)). 1
1, 3, 7, 11, 15, 23, 31, 35, 39, 47, 55, 59, 63, 71, 79, 83, 95, 107, 111, 119, 127, 131, 143, 159, 167, 175, 179, 191, 199, 207, 215, 223, 239, 251, 255, 263, 279, 287, 299, 311, 319, 323, 335, 351, 359, 383, 391, 395, 399, 407, 415, 419, 431, 439, 447, 455, 467, 479 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..58.

FORMULA

a(n) = 2 * A279105(n) - 1.

EXAMPLE

a(3) = 7 = 2 * A279105(3) - 1;

21 is not in the sequence since 11=(21+1)/2 is not in A174793.

MATHEMATICA

a174973Q[n_] := Module[{d=Divisors[n]}, Select[Rest[d] - 2*Most[d], #>0&]=={}]

a279106[n_]:=2*Select[Range[n], a174973Q] - 1

a279106[250] (* sequence data *)

CROSSREFS

Cf. A174973, A237270, A237271, A237593, A279105.

Sequence in context: A095100 A036994 A243115 * A172306 A112714 A231348

Adjacent sequences:  A279103 A279104 A279105 * A279107 A279108 A279109

KEYWORD

nonn

AUTHOR

Hartmut F. W. Hoft, Dec 06 2016

STATUS

approved

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Last modified March 21 18:59 EDT 2019. Contains 321382 sequences. (Running on oeis4.)