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A182557 a(n) = a(n-1)*2 + floor(sqrt(a(n-2))). 2
0, 1, 2, 5, 11, 24, 51, 106, 219, 448, 910, 1841, 3712, 7466, 14992, 30070, 60262, 120697, 241639, 483625, 967741, 1936177, 3873337, 7748065, 15498098, 30998979, 62001894, 124009355, 248026584, 496064303, 992144354, 1984310980, 3968653458, 7937351461, 15874765919 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..34.

FORMULA

a(0)=0, a(1)=1, a(n) = a(n-1)*2 + floor(sqrt(a(n-2))).

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.

Sequence in context: A091360 A294378 A090764 * A027934 A134389 A286945

Adjacent sequences:  A182554 A182555 A182556 * A182558 A182559 A182560

KEYWORD

nonn

AUTHOR

Alex Ratushnyak, May 05 2012

STATUS

approved

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Last modified February 20 16:25 EST 2018. Contains 299380 sequences. (Running on oeis4.)