The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A051809 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A051809

Numbers with nonzero multiplicative digital root 7.
(history; published version)

#8 by Harvey P. Dale at Fri Jan 18 14:11:09 EST 2019

STATUS

editing

approved

#7 by Harvey P. Dale at Fri Jan 18 14:11:06 EST 2019

MATHEMATICA

Select[Range[2500], NestWhile[Times@@(IntegerDigits[#]/.(0->1))&, #, #>9&] == 7&] (* Harvey P. Dale, Jan 18 2019 *)

STATUS

approved

editing

#6 by Charles R Greathouse IV at Mon Feb 13 21:07:04 EST 2017

STATUS

editing

approved

#5 by Charles R Greathouse IV at Mon Feb 13 21:06:42 EST 2017

LINKS

<a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.

STATUS

approved

editing

#4 by N. J. A. Sloane at Wed Jun 11 17:24:22 EDT 2014

AUTHOR

_Dan Hoey (Hoey(AT)AIC.NRL.Navy.Mil), _, Dec 09 1999

Discussion

Wed Jun 11

17:24

OEIS Server: https://oeis.org/edit/global/2229

#3 by N. J. A. Sloane at Fri May 16 03:00:00 EDT 2003

CROSSREFS

Part of histogram of A051802.

KEYWORD

nonn,easy,base,new

AUTHOR

Dan Hoey (Hoey@(AT)AIC.NRL.Navy.Mil), Dec 09 1999

#2 by N. J. A. Sloane at Mon May 08 03:00:00 EDT 2000

KEYWORD

nonn,easy,base,new

AUTHOR

Dan Hoey <(Hoey@AIC.NRL.Navy.Mil>), Dec 09 1999

#1 by N. J. A. Sloane at Sat Dec 11 03:00:00 EST 1999

NAME

Numbers with nonzero multiplicative digital root 7.

DATA

7, 17, 70, 71, 107, 117, 170, 171, 257, 275, 527, 572, 700, 701, 710, 711, 725, 752, 1007, 1017, 1070, 1071, 1107, 1117, 1170, 1171, 1257, 1275, 1527, 1572, 1700, 1701, 1710, 1711, 1725, 1752, 2057, 2075, 2157, 2175

OFFSET

1,1

FORMULA

A051802^-1(7)

CROSSREFS

Part of histogram of A051802

KEYWORD

nonn,easy,base

AUTHOR

Dan Hoey <Hoey@AIC.NRL.Navy.Mil>

STATUS

approved