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%I #18 Jun 30 2020 03:15:07
%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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