The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A261224

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A261224

a(n) = number of steps needed to reach (n^2)-1 when starting from k = ((n+1)^2)-1 and repeatedly applying the map that replaces k with k - A053610(k), where A053610(k) = the number of positive squares that sum to k using the greedy algorithm.
(history; published version)

#16 by Jon E. Schoenfield at Thu Mar 30 21:57:06 EDT 2017

STATUS

editing

approved

#15 by Jon E. Schoenfield at Thu Mar 30 21:57:02 EDT 2017

NAME

a(n) = number of steps needed to reach (n^2)-1 when starting from k = ((n+1)^2)-1 and repeatedly applying the map that replaces k by with k - A053610(k), where A053610(k) = the number of positive squares that sum to k using the greedy algorithm.

STATUS

approved

editing

#14 by N. J. A. Sloane at Thu Sep 08 18:51:53 EDT 2016

STATUS

reviewed

approved

#13 by G. C. Greubel at Thu Sep 08 17:37:53 EDT 2016

STATUS

proposed

reviewed

#12 by Michael De Vlieger at Thu Sep 08 14:22:08 EDT 2016

STATUS

editing

proposed

#11 by Michael De Vlieger at Thu Sep 08 14:21:38 EDT 2016

MATHEMATICA

Table[-1 + Length@ NestWhileList[# - Block[{m = #, c = 1}, While[a = (# - Floor[Sqrt@ #]^2) &@ m; a != 0, c++; m = a]; c] &, ((n + 1)^2) - 1, # != n^2 - 1 &], {n, 91}] (* Michael De Vlieger, Sep 08 2016, after Jud McCranie at A053610 *)

STATUS

approved

editing

Discussion

Thu Sep 08

14:22

Michael De Vlieger: Edited in conjunction with A276581.

#10 by N. J. A. Sloane at Thu Aug 20 07:42:11 EDT 2015

STATUS

proposed

approved

#9 by Antti Karttunen at Mon Aug 17 06:35:15 EDT 2015

STATUS

editing

proposed

#8 by Antti Karttunen at Sun Aug 16 15:11:43 EDT 2015

CROSSREFS

Cf. also A260734, A261229.

#7 by Antti Karttunen at Sun Aug 16 12:49:40 EDT 2015

NAME

a(n) = number of steps needed to reach 0 (n^2)-1 when starting from k = (n*(n+1)^2)-1 and repeatedly applying the map that replaces k by k - A053610(k), where A053610(k) = the number of positive squares that sum to k using the greedy algorithm.