The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A023104

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

A023104

(2^n)-th digit of infinite string 12345678910111213141516...
(history; published version)

#18 by Michel Marcus at Mon Dec 01 00:21:46 EST 2014

STATUS

reviewed

approved

#17 by Wesley Ivan Hurt at Sun Nov 30 21:38:59 EST 2014

STATUS

proposed

reviewed

#16 by Jon E. Schoenfield at Sun Nov 30 21:34:11 EST 2014

STATUS

editing

proposed

#15 by Jon E. Schoenfield at Sun Nov 30 21:34:09 EST 2014

MATHEMATICA

almostNatural[n_, b_] := Block[{m = 0, d = n, i = 1, l, p}, While[m <= d, l = m; m = (b - 1) i*b^(i - 1) + l; i++]; i--; p = Mod[d - l, i]; q = Floor[(d - l)/i] + b^(i - 1); If[p != 0, IntegerDigits[q, b][[p]], Mod[q - 1, b]]]; Array[ almostNatural[2^#, 10] &, 105, 0] (* Robert G. Wilson v, Jun 27 2014 and modified July Jul 15 2014 *)

STATUS

approved

editing

#14 by N. J. A. Sloane at Wed Jul 16 15:46:38 EDT 2014

STATUS

proposed

approved

#13 by Robert G. Wilson v at Tue Jul 15 16:24:06 EDT 2014

STATUS

editing

proposed

#12 by Robert G. Wilson v at Tue Jul 15 16:23:59 EDT 2014

MATHEMATICA

falmostNatural[n_, b_] := Block[{m = 0, d = n, i = 1, l, p}, While[m <= d, l = m; m = 9 (b - 1) i*10b^(i - 1) + l; i++]; i--; p = Mod[d - l, i]; q = Floor[(d - l)/i] + 10b^(i - 1); If[ p != 0, IntegerDigits[q, b][[p]], Mod[q - 1, 10b]]]; Array[ falmostNatural[2^#, 10] &, 105, 0] (* Robert G. Wilson v, Jun 27 2014 and modified July 15 2014 *)

STATUS

approved

editing

#11 by N. J. A. Sloane at Sat Jun 28 08:25:53 EDT 2014

STATUS

proposed

approved

#10 by Robert Israel at Fri Jun 27 19:09:57 EDT 2014

STATUS

editing

proposed

#9 by Robert Israel at Fri Jun 27 19:09:50 EDT 2014

FORMULA

a(n) = A007376(2^n). - Robert Israel, Jun 27 2014

STATUS

proposed

editing