The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A046467 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A046467

Numbers k such that the concatenation of numbers from 1 to k is the product of 8 primes (not necessarily distinct).
(history; published version)

#23 by Susanna Cuyler at Sat Apr 10 16:59:40 EDT 2021

STATUS

proposed

approved

#22 by Michel Marcus at Sat Apr 10 16:29:34 EDT 2021

STATUS

editing

proposed

#21 by Michel Marcus at Sat Apr 10 16:29:31 EDT 2021

KEYWORD

nonn,hard,base,hard,more,changed

#20 by Michel Marcus at Sat Apr 10 16:29:09 EDT 2021

LINKS

Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_008.htm">Puzzle 8. Primes by Listing</a>, The Prime Puzzles & Problems Connection.

MATHEMATICA

Select[Range[100], PrimeOmega@FromDigits@Flatten@IntegerDigits@Range@# == 8 &] (* _Robert Price_, Oct 11 2019 *)

PrimeOmega@FromDigits@Flatten@IntegerDigits@Range@# == 8 &] (* Robert Price, Oct 11 2019 *)

STATUS

proposed

editing

#19 by Sean A. Irvine at Sat Apr 10 16:26:09 EDT 2021

STATUS

editing

proposed

#18 by Sean A. Irvine at Sat Apr 10 16:25:57 EDT 2021

DATA

6, 21, 27, 35, 48, 53, 60, 62, 66, 92, 106, 108, 117

EXTENSIONS

a(9)-a(13) from Sean A. Irvine, Apr 10 2021

STATUS

approved

editing

#17 by Michel Marcus at Wed Oct 16 01:58:17 EDT 2019

STATUS

reviewed

approved

#16 by Joerg Arndt at Wed Oct 16 01:35:13 EDT 2019

STATUS

proposed

reviewed

#15 by Michel Marcus at Wed Oct 16 00:40:52 EDT 2019

STATUS

editing

proposed

#14 by Michel Marcus at Wed Oct 16 00:40:43 EDT 2019

OFFSET

0,1,1

STATUS

proposed

editing

Discussion

Wed Oct 16

00:40

Michel Marcus: offset 1