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%I #30 Sep 22 2023 05:21:57
%S 0,2,5,7,10,13,15,18,20,23,26,28,31,34,36,39,41,44,47,49,52,54,57,60,
%T 62,65,68,70,73,75,78,81,83,86,89,91,94,96,99,102,104,107,109,112,115,
%U 117,120,123,125,128,130,133,136,138,141,143,146,149,151,154,157,159,162
%N Terms a(k) of A073869 for which a(k-1), a(k) and a(k+1) are distinct.
%C Apart from the initial 0, is this the same as A001950? - Alec Mihailovs (alec(AT)mihailovs.com), Jul 23 2007
%C Identical to n + A066096(n)? - Ed Russell (times145(AT)hotmail.com), May 09 2009
%H G. C. Greubel, <a href="/A090909/b090909.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n) = floor(phi^2*n), where phi = (1+sqrt(5))/2. - _Gary Detlefs_, Mar 10 2011
%t (* First program *)
%t A002251= Fold[Append[#1, #2 Ceiling[#2/GoldenRatio] -Total[#1]] &, {1}, Range[2, 500]] - 1; (* Birkas Gyorgy's code of A019444, modified *)
%t A090909= Join[{0}, Select[Partition[A002251, 2, 1], #[[2]] > #[[1]] &][[All, 2]]] (* _G. C. Greubel_, Sep 12 2023 *)
%t (* Second program *)
%t Floor[GoldenRatio^2*Range[0,80]] (* _G. C. Greubel_, Sep 12 2023 *)
%o (Magma) [Floor((3+Sqrt(5))*n/2): n in [0..80]]; // _G. C. Greubel_, Sep 12 2023
%o (SageMath) [floor(golden_ratio^2*n) for n in range(81)] # _G. C. Greubel_, Sep 12 2023
%Y Cf. A001622, A001950, A002251, A005206, A073869, A090908.
%Y Cf. A004919, A004920, A004921, A004922, A004923, A004924, A004925.
%Y Cf. A004926, A004927, A004928, A004929, A004930, A004931, A004932.
%Y Cf. A004933, A004934, A004935, A004976, A066096.
%K nonn
%O 0,2
%A _Amarnath Murthy_, Dec 14 2003
%E More terms from _R. J. Mathar_, Sep 29 2017
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