The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A217395 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A217395

Numbers starting with 3.
(history; published version)

#30 by Alois P. Heinz at Wed Sep 11 11:45:08 EDT 2024

STATUS

reviewed

approved

#29 by Joerg Arndt at Wed Sep 11 10:58:05 EDT 2024

STATUS

proposed

reviewed

#28 by Chai Wah Wu at Wed Sep 11 09:26:44 EDT 2024

STATUS

editing

proposed

#27 by Chai Wah Wu at Wed Sep 11 09:26:37 EDT 2024

PROG

(Python)

def A217395(n): return n+26*10**(len(str(9*n-8))-1)//9 # Chai Wah Wu, Sep 11 2024

STATUS

approved

editing

#26 by Michael De Vlieger at Wed May 17 08:35:45 EDT 2023

STATUS

reviewed

approved

#25 by Kevin Ryde at Wed May 17 04:14:14 EDT 2023

STATUS

proposed

reviewed

Discussion

Wed May 17

08:14

Alan Michael Gómez Calderón: Strangely using pari-gp (Version 2.16.0) I only saw a difference at n = 112 for both formulas (9*n-8, 9*n), working the same after precision set over to \p 10 for 1<=n<=50000.

#24 by Kevin Ryde at Wed May 17 04:13:44 EDT 2023

STATUS

editing

proposed

#23 by Kevin Ryde at Wed May 17 04:09:39 EDT 2023

FORMULA

a(n) = n + (26*10^floor(log_10(9*n-8))-8)/9. - Alan Michael Gómez Calderón, May 16 2023

STATUS

proposed

editing

Discussion

Wed May 17

04:13

Kevin Ryde: Actually, I see for my program code I used 9*n since it has the same floor log_10 as 9*n-8 does.  (Because 100..008 is the smallest multiple of 9 >= 10^k and -8 doesn't cause it to drop below 10^k.)

#22 by Michel Marcus at Tue May 16 10:00:05 EDT 2023

STATUS

editing

proposed

#21 by Michel Marcus at Tue May 16 10:00:02 EDT 2023

FORMULA

a(n) = n+(26*10^floor(log_10(9*n-8))-8)/9. -_ _Alan Michael Gómez Calderón_, May 16 2023

STATUS

proposed

editing