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Revision History for A131295

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Showing entries 1-10 | older changes

A131295

a(n)=ds_4(a(n-1))+ds_4(a(n-2)), a(0)=0, a(1)=1; where ds_4=digital sum base 4.
(history; published version)

#14 by Harvey P. Dale at Mon Jul 30 18:07:29 EDT 2018

STATUS

editing

approved

#13 by Harvey P. Dale at Mon Jul 30 18:07:24 EDT 2018

LINKS

Harvey P. Dale, <a href="/A131295/b131295.txt">Table of n, a(n) for n = 0..1000</a>

STATUS

approved

editing

#12 by Harvey P. Dale at Mon Jul 30 18:01:47 EDT 2018

STATUS

editing

approved

#11 by Harvey P. Dale at Mon Jul 30 18:01:43 EDT 2018

MATHEMATICA

nxt[{a_, b_}]:={b, Total[IntegerDigits[a, 4]]+Total[IntegerDigits[b, 4]]}; NestList[ nxt, {0, 1}, 110][[All, 1]] (* Harvey P. Dale, Jul 30 2018 *)

STATUS

approved

editing

#10 by Jon E. Schoenfield at Sat Jul 11 16:45:10 EDT 2015

STATUS

editing

approved

#9 by Jon E. Schoenfield at Sat Jul 11 16:45:08 EDT 2015

COMMENTS

The digital sum analogue analog (in base 4) of the Fibonacci recurrence.

STATUS

approved

editing

#8 by N. J. A. Sloane at Sat Oct 12 21:32:55 EDT 2013

STATUS

editing

approved

#7 by N. J. A. Sloane at Sat Oct 12 21:32:53 EDT 2013

LINKS

<a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>

STATUS

approved

editing

#6 by Russ Cox at Sat Mar 31 13:21:03 EDT 2012

COMMENTS

a(n) and Fib(n)=A000045(n) are congruent modulo 3 which implies that (a(n) mod 3) is equal to (Fib(n) mod 3)=A082115(n-1) (for n>0). Thus (a(n) mod 3) is periodic with the Pisano period = A001175(3)=8 too. - Hieronymus Fischer (_Hieronymus. Fischer(AT)gmx.de)_

AUTHOR

Hieronymus Fischer (_Hieronymus. Fischer(AT)gmx.de), _, Jun 27 2007

Discussion

Sat Mar 31

13:21

OEIS Server: https://oeis.org/edit/global/882

#5 by N. J. A. Sloane at Fri Nov 12 07:22:15 EST 2010

STATUS

reviewed

approved