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A144178 (2*2=4, 2*3=6, 2*4=8, 2*5=10, 2*6=12, 2*7=14, 2*8=16, 2*9=18, 2*10=20, 3*2=6,..) becomes (abs(2*2, 4*2, 3*6, 2*4, 8*2, 5*10, 2*6, 12*2, 7*14, 2*8, 16*2, 9*18, 2*10, 20*3, 2*6,..)) . 0

%I

%S 4,8,18,8,16,50,12,24,98,16,32,162,20,60,12,9,27,48,15,45,108,21,63,

%T 192,27,81,300,8,32,36,16,64,100,24,96,196,32,128,324,40,200,20,15,75,

%U 80,25,125,180,35,175,320,45,225,500,12,72,54,24,144,150,36,216,294,48,288

%N (2*2=4, 2*3=6, 2*4=8, 2*5=10, 2*6=12, 2*7=14, 2*8=16, 2*9=18, 2*10=20, 3*2=6,..) becomes (abs(2*2, 4*2, 3*6, 2*4, 8*2, 5*10, 2*6, 12*2, 7*14, 2*8, 16*2, 9*18, 2*10, 20*3, 2*6,..)) .

%C (.., 9*9=81, 9*10=90, 10*2=20, 10*3=30, 10*4=40, 10*5=50,

%C 10*6=60, 10*7=70, 10*8=80, 10*9=90, 10*10=100, 11*2=22,..) becomes

%C (abs(.., 9*9, 81*9, 10*90, 10*2, 20*10, 3*30, 10*4, 40*10, 5*50, 10*6,

%C 60*10, 7*70, 10*8, 80*10, 9*90, 10*10, 100*11, 2*22,..)).

%e 2*2=4=a(1).

%e 4*2=8=a(2).

%e 3*6=18=a(3).

%e 2*4=8=a(4).

%e 8*2=16=a(5).

%e 5*10=50=a(6), etc.

%Y Cf. A143677.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Nov 19 2008

%E Corrected (a 175 replaced by 225) by _R. J. Mathar_, Apr 29 2010

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Last modified October 22 09:37 EDT 2021. Contains 348160 sequences. (Running on oeis4.)