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A260987 Record values in A008480. 3
1, 2, 3, 4, 6, 12, 20, 30, 60, 105, 120, 140, 180, 210, 280, 420, 504, 840, 1120, 1512, 1680, 2520, 3780, 5040, 6300, 7560, 9240, 12600, 13860, 15120, 15840, 27720, 34650, 37800, 55440, 83160, 102960, 110880, 138600, 180180, 205920, 216216, 240240, 332640 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..2011 (terms 1..80 from Reinhard Zumkeller)

FORMULA

a(n) = A008480(A260633(n)).

EXAMPLE

.   n | x = A260633(n)        | y = a(n)             | [x/y] | x mod y

. ----+-----------------------+----------------------+-------+---------

.   1 |     1 | 1             |    1 | 1             |    1  |      0

.   2 |     6 | 2*3           |    2 | 2             |    3  |      0

.   3 |    12 | 2^2*3         |    3 | 3             |    4  |      0

.   4 |    24 | 2^3*3         |    4 | 2^2           |    6  |      0

.   5 |    30 | 2*3*5         |    6 | 2*3           |    5  |      0

.   6 |    60 | 2^2*3*5       |   12 | 2^2*3         |    5  |      0

.   7 |   120 | 2^3*3*5       |   20 | 2^2*5         |    6  |      0

.   8 |   180 | 2^2*3^2*5     |   30 | 2*3*5         |    6  |      0

.   9 |   360 | 2^3*3^2*5     |   60 | 2^2*3*5       |    6  |      0

.  10 |   720 | 2^4*3^2*5     |  105 | 3*5*7         |    6  |     90

.  11 |   840 | 2^3*3*5*7     |  120 | 2^3*3*5       |    7  |      0

.  12 |  1080 | 2^3*3^3*5     |  140 | 2^2*5*7       |    7  |    100

.  13 |  1260 | 2^2*3^2*5*7   |  180 | 2^2*3^2*5     |    7  |      0

.  14 |  1680 | 2^4*3*5*7     |  210 | 2*3*5*7       |    8  |      0

.  15 |  2160 | 2^4*3^3*5     |  280 | 2^3*5*7       |    7  |    200

.  16 |  2520 | 2^3*3^2*5*7   |  420 | 2^2*3*5*7     |    6  |      0

.  17 |  4320 | 2^5*3^3*5     |  504 | 2^3*3^2*7     |    8  |    288

.  18 |  5040 | 2^4*3^2*5*7   |  840 | 2^3*3*5*7     |    6  |      0

.  19 |  7560 | 2^3*3^3*5*7   | 1120 | 2^5*5*7       |    6  |    840

.  20 | 10080 | 2^5*3^2*5*7   | 1512 | 2^3*3^3*7     |    6  |   1008

.  21 | 12600 | 2^3*3^2*5^2*7 | 1680 | 2^4*3*5*7     |    7  |    840

.  22 | 15120 | 2^4*3^3*5*7   | 2520 | 2^3*3^2*5*7   |    6  |      0

.  23 | 25200 | 2^4*3^2*5^2*7 | 3780 | 2^2*3^3*5*7   |    6  |   2520

.  24 | 30240 | 2^5*3^3*5*7   | 5040 | 2^4*3^2*5*7   |    6  |      0

.  25 | 45360 | 2^4*3^4*5*7   | 6300 | 2^2*3^2*5^2*7 |    7  |   1260 .

PROG

(Haskell)

a260987 n = a260987_list !! (n-1)

(a260987_list, a260633_list) = unzip $ f 1 0 where

   f x r = if y > r then (y, x) : f (x + 1) y else f (x + 1) r

           where y = a008480 x

CROSSREFS

Cf. A008480, A260633.

Sequence in context: A221846 A018343 A242459 * A102462 A277408 A018369

Adjacent sequences:  A260984 A260985 A260986 * A260988 A260989 A260990

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Nov 18 2015

STATUS

approved

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Last modified November 15 11:18 EST 2019. Contains 329144 sequences. (Running on oeis4.)