The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A029527 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A029527

Numbers k such that k divides the (left) concatenation of all numbers <= k written in base 10 (most significant digit on right).
(history; published version)

#23 by Susanna Cuyler at Mon Jul 26 01:46:37 EDT 2021

STATUS

reviewed

approved

#22 by Joerg Arndt at Mon Jul 26 01:21:08 EDT 2021

STATUS

proposed

reviewed

#21 by Jon E. Schoenfield at Sun Jul 25 23:06:07 EDT 2021

STATUS

editing

proposed

#20 by Jon E. Schoenfield at Sun Jul 25 23:06:06 EDT 2021

NAME

Numbers n k such that n k divides the (left) concatenation of all numbers <= n k written in base 10 (most significant digit on right).

STATUS

approved

editing

#19 by N. J. A. Sloane at Sat Dec 05 23:36:33 EST 2020

STATUS

proposed

approved

#18 by Jinyuan Wang at Sat Dec 05 22:25:29 EST 2020

STATUS

editing

proposed

#17 by Jinyuan Wang at Sat Dec 05 22:25:12 EST 2020

COMMENTS

No more terms < 10^7. [- _Lars Blomberg, _, Sep 12 2011]

PROG

(PARI) lista(nn, m=10) = my(c, s, t); for(k=1, nn, t+=m^c*s=fromdigits(Vecrev(digits(k, m)), m); c+=logint(s, m)+1; if(t%k==0, print1(k, ", "))); \\ Jinyuan Wang, Dec 05 2020

STATUS

approved

editing

#16 by Susanna Cuyler at Fri Mar 13 16:44:57 EDT 2020

STATUS

proposed

approved

#15 by Robert Price at Fri Mar 13 16:16:58 EDT 2020

STATUS

editing

proposed

#14 by Robert Price at Fri Mar 13 16:16:55 EDT 2020

MATHEMATICA

b = 10; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[IntegerDigits[IntegerReverse[#, b], b], c], b], #] &] (* Robert Price, Mar 13 2020 *)

KEYWORD

nonn,base,more

STATUS

approved

editing