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 A182558 a(n) = a(n-1)*2 - floor(sqrt(a(n-2))). 1
 0, 1, 2, 3, 5, 9, 16, 29, 54, 103, 199, 388, 762, 1505, 2983, 5928, 11802, 23528, 46948, 93743, 187270, 374234, 748036, 1495461, 2990058, 5978894, 11956059, 23909673, 47815889, 95626889, 191246864, 382483950, 764954071, 1529888585, 3059749513 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Harvey P. Dale, Table of n, a(n) for n = 0..1000 FORMULA a(0)=0, a(1)=1, a(n) = a(n-1)*2 - floor(sqrt(a(n-2))). MATHEMATICA nxt[{a_, b_}]:={b, 2b-Floor[Sqrt[a]]}; NestList[nxt, {0, 1}, 40][[All, 1]] (* Harvey P. Dale, Apr 29 2017 *) PROG (Python) import math prpr = 0 prev = 1 for n in range(55): .  current = prev*2 - int(math.sqrt(prpr)) .  print prpr, .  prpr = prev .  prev = current CROSSREFS Cf. A076677, A076678, A182557. Sequence in context: A000050 A050253 A198518 * A298204 A265581 A107250 Adjacent sequences:  A182555 A182556 A182557 * A182559 A182560 A182561 KEYWORD nonn AUTHOR Alex Ratushnyak, May 05 2012 STATUS approved

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Last modified August 10 07:14 EDT 2020. Contains 336368 sequences. (Running on oeis4.)