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A333978 Numbers of the form b_1 * b_2 * ... * b_t, where b_1 = 1 and b_(i + 1) - b_i = 0 or 1. 1
1, 2, 4, 6, 8, 12, 16, 18, 24, 32, 36, 48, 54, 64, 72, 96, 108, 120, 128, 144, 162, 192, 216, 240, 256, 288, 324, 360, 384, 432, 480, 486, 512, 576, 600, 648, 720, 768, 864, 960, 972, 1024, 1080, 1152, 1200, 1296, 1440, 1458, 1536, 1728, 1800, 1920, 1944, 2048 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

This sequence is the distinct values in A284001, sorted.

If m and k are in this sequence, then so is their product m*k.

If a prime p divides a(n), then so does p!.

A001013 is a subsequence.

LINKS

Peter Kagey, Table of n, a(n) for n = 1..1000

EXAMPLE

The first 11 terms can be written as

1  = 1

2  = 1 * 2

4  = 1 * 2 * 2

6  = 1 * 2 * 3

8  = 1 * 2 * 2 * 2

12 = 1 * 2 * 2 * 3

16 = 1 * 2 * 2 * 2 * 2

18 = 1 * 2 * 3 * 3

24 = 1 * 2 * 3 * 4 or 1 * 2 * 2 * 2 * 3

32 = 1 * 2 * 2 * 2 * 2 * 2

36 = 1 * 2 * 2 * 3 * 3

CROSSREFS

Cf. A001013, A284001, A334636.

Sequence in context: A145853 A318782 A064527 * A007694 A322492 A332276

Adjacent sequences:  A333975 A333976 A333977 * A333979 A333980 A333981

KEYWORD

nonn

AUTHOR

Peter Kagey, Sep 20 2020

STATUS

approved

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Last modified May 22 09:50 EDT 2022. Contains 353949 sequences. (Running on oeis4.)