The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A243974

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A243974

Integers n not of form 3m+1 such that for any integer k>0, n*10^k-1 has a divisor in the set { 7, 11, 13, 37 }.
(history; published version)

#54 by Charles R Greathouse IV at Mon Apr 25 11:50:02 EDT 2016

PROG

( PFGW & SCRIPT )

Discussion

Mon Apr 25

11:50

OEIS Server: https://oeis.org/edit/global/2505

#53 by N. J. A. Sloane at Sat Jul 12 16:21:26 EDT 2014

STATUS

proposed

approved

#52 by Pierre CAMI at Fri Jul 11 13:14:01 EDT 2014

STATUS

editing

proposed

#51 by Pierre CAMI at Fri Jul 11 13:13:47 EDT 2014

PROG

IF (k*10^n-1)%3==0 THEN GOTO loop2

STATUS

proposed

editing

#50 by Pierre CAMI at Wed Jul 09 11:34:48 EDT 2014

STATUS

editing

proposed

#49 by Jens Kruse Andersen at Wed Jul 09 08:32:07 EDT 2014

NAME

Integers n not of form 3m+1 such that for any integer k>0 , n*10^k-1 has a divisor in the set { 3, 7, 11, 13, 37 }.

COMMENTS

If n is of form 3m+1 then n*10^k-1 is always divisible by 3. - Jens Kruse Andersen, Jul 09 2014

EXAMPLE

10176*10^k-1 is divisible by 11 for k of form 6m, 6m+2, 6m+4, by 7 for k of form 6m+1, by 37 for 6m+3 (and also 6m), and by 13 for 6m+5. This covers all k. {7, 11, 13, 37} is called a covering set. - Jens Kruse Andersen, Jul 09 2014

CROSSREFS

Cf. A076337, A243969, A243974, A244070, A244071, A244072, A244073, A244074, A244076.

EXTENSIONS

Definition corrected by Jens Kruse Andersen, Jul 09 2014

STATUS

proposed

editing

#48 by Pierre CAMI at Wed Jul 09 03:32:44 EDT 2014

STATUS

editing

proposed

#47 by Pierre CAMI at Wed Jul 09 03:32:38 EDT 2014

NAME

Integers n such that for any integer k>0 n*10n10^k-1 has a divisor in the set { 3, 7, 11, 13, 37 }.

STATUS

proposed

editing

#46 by Pierre CAMI at Wed Jul 09 03:31:17 EDT 2014

STATUS

editing

proposed

#45 by Pierre CAMI at Wed Jul 09 02:39:25 EDT 2014

COMMENTS

For n>24 a(n) = a(n-24) + 111111. The , the first 24 values are in the data.

STATUS

proposed

editing