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A168294 Carryless product n times n+1. 7


%S 0,2,6,2,0,0,2,6,2,90,110,132,156,172,190,110,132,156,172,280,420,462,

%T 406,442,480,420,462,406,442,670,930,992,956,912,970,930,992,956,912,

%U 260,640,622,606,682,660,640,622,606,682,50,550,552,556,552,550,550,552,556,552

%N Carryless product n times n+1.

%H David Applegate, Marc LeBrun and N. J. A. Sloane, <a href="http://neilsloane.com/doc/carry1.pdf">Carryless Arithmetic (I): The Mod 10 Version</a>.

%H <a href="/index/Ca#CARRYLESS">Index entries for sequences related to carryless arithmetic</a>

%o (Python)

%o def A168294(n):

%o s, t = [int(d) for d in str(n)], [int(d) for d in str(n+1)]

%o l, m = len(s), len(t)

%o u = [0]*(l+m-1)

%o for i in range(l):

%o for j in range(m):

%o u[i+j] = (u[i+j] + s[i]*t[j]) % 10

%o return int("".join(str(d) for d in u)) # _Chai Wah Wu_, Jun 30 2020

%Y Cf. A004520, A059729.

%K nonn,base

%O 0,2

%A _David Applegate_, _Marc LeBrun_ and _N. J. A. Sloane_, Jul 06 2010

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Last modified April 20 19:10 EDT 2021. Contains 343137 sequences. (Running on oeis4.)