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A227289 Smallest m such that GCD(A227113(m+1),A227113(m)) = n. 2
1, 2, 4, 10, 6, 177, 8, 514, 500, 349, 14, 4791, 16, 5949, 1623, 863, 20, 2629, 22, 5113, 2043, 3211, 28, 7347, 4593, 11911, 1647, 12819, 34, 27325, 36, 15755, 34527, 29319, 5459, 2797, 42, 24535, 20145, 15511, 46, 26523, 48, 64895, 13335, 40769, 54, 43835, 184041 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A227288(a(n)) = n and A227288(m) <> n for m < a(n).

LINKS

Table of n, a(n) for n=1..49.

EXAMPLE

.   n |   a(n) | A227288(a(n)) = GCD(A227113(a(n)),A227113(a(n)+1))

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

.   1 |     1  |            1  =  GCD(1,2)

.   2 |     2  |            2  =  GCD(2,4)

.   3 |     4  |            3  =  GCD(3,6)

.   4 |    10  |            4  =  GCD(8,12)

.   5 |     6  |            5  =  GCD(5,10)

.   6 |   177  |            6  =  GCD(168,162)

.   7 |     8  |            7  =  GCD(7,14)

.   8 |   514  |            8  =  GCD(472,480)

.   9 |   500  |            9  =  GCD(459,468)

.  10 |   349  |           10  =  GCD(330,320)

.  11 |    14  |           11  =  GCD(11,22)

.  12 |  4791  |           12  =  GCD(4524,4512) .

PROG

(Haskell)

import Data.List (elemIndex); import Data.Maybe (fromJust)

a227289 = (+ 1) . fromJust . (`elemIndex` a227288_list)

CROSSREFS

Sequence in context: A159585 A130334 A320537 * A200742 A178729 A124108

Adjacent sequences:  A227286 A227287 A227288 * A227290 A227291 A227292

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 05 2013

STATUS

approved

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Last modified March 26 04:32 EDT 2019. Contains 321481 sequences. (Running on oeis4.)