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A340792 List in which n appears ceiling(d(n)/2) = A038548(n) times, where d(n) is the number of divisors of n. 3
1, 2, 3, 4, 4, 5, 6, 6, 7, 8, 8, 9, 9, 10, 10, 11, 12, 12, 12, 13, 14, 14, 15, 15, 16, 16, 16, 17, 18, 18, 18, 19, 20, 20, 20, 21, 21, 22, 22, 23, 24, 24, 24, 24, 25, 25, 26, 26, 27, 27, 28, 28, 28, 29, 30, 30, 30, 30, 31, 32, 32, 32, 33, 33, 34, 34, 35, 35, 36, 36, 36, 36, 36 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The numbers in A075362 arranged in numerical order.

LINKS

Table of n, a(n) for n=1..73.

Charles Kusniec, Bijection between OEIS sequence A340792 and the positive Triangular Multiplication Table

FORMULA

T(n,k) = A161906(n,k) * A340791(n,k).

EXAMPLE

Array begins:

   1

   2

   3

   4  4

   5

   6  6

   7

   8  8

   9  9

  10 10

  11

  12 12 12

  13

  14 14

  15 15

  16 16 16

  17

  18 18 18

  19

  20 20 20

  21 21

  22 22

  23

  24 24 24 24

PROG

(PARI) row(n) = my(d=divisors(n), r1=select(x->(x<=sqrt(n)), d), r2=Vecrev(select(x->(x>=sqrt(n)), d))); vector(#r1, k, r1[k]*r2[k]); \\ Michel Marcus, Jan 22 2021

CROSSREFS

Cf. A038548 (row lengths), A075362, A161906, A340791, A061017 (comparable array).

Sequence in context: A099801 A099802 A196266 * A112232 A168389 A039708

Adjacent sequences:  A340789 A340790 A340791 * A340793 A340794 A340795

KEYWORD

nonn,tabf

AUTHOR

Charles Kusniec, Jan 21 2021

STATUS

approved

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Last modified August 1 07:45 EDT 2021. Contains 346384 sequences. (Running on oeis4.)