A299174 The even positive integers.

2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144

Offset

1,1

Comments

Possible periods of Post's {00, 1101} tag system. - Charles R Greathouse IV, Dec 13 2021

Numbers m such that 2^m - m is divisible by 2. - Bernard Schott, Dec 15 2021

Links

Table of n, a(n) for n=1..72.

Joss Langford, Simple Integer Sequences

James B. Shearer, Periods of strings, American Scientist Vol. 84, No. 3 (May-June 1996), p. 207. (See final page of pdf, and see also pp. 3-4 for an introduction.)

Index entries for linear recurrences with constant coefficients, signature (2,-1).

Formula

a(n) = 2*n, n >= 1.

G.f.: 2*x/(1 - x)^2; corrected by Ilya Gutkovskiy, Mar 29 2018

Maple

A299174 := n->2*n;

Mathematica

Range[2, 180, 2]

Prog

(R) seq(2, 180, 2)
(PARI) a(n)=2*n \\ Charles R Greathouse IV, Dec 13 2021

Crossrefs

Equals A005843 without the leading zero.

Bisection of A000027. Complement of A004273. - Omar E. Pol, Feb 25 2018

First row of A083140.

Cf. A005408.

Cf. A000325, A047257, A349767.

Essentially the same as A163300, A103517, A051755, A005843 and A004277.

Numbers k that can be written as the sum of j divisors of k (not necessarily distinct) for j=1..10: A000027 (j=1), this sequence (j=2), A355200 (j=3), A354591 (j=4), A355641 (j=5), A356609 (j=6), A356635 (j=7), A356657 (j=8), A356659 (j=9), A356660 (j=10).

Sequence in context: A317440 A076032 A004277 * A122080 A105360 A306720

Adjacent sequences: A299171 A299172 A299173 * A299175 A299176 A299177

Keyword

nonn,easy

Author

Joss Langford, Feb 04 2018

Status

approved