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 A077760 Nonsquares which in at least two ways are the product of two numbers with the same digits (leading zeros are forbidden). 1

%I

%S 101556,121968,124012,133875,144648,172900,185472,226800,352170,

%T 433755,2096640,3779136,4264416,5166504,5333680,5448960,5651919,

%U 5894784,5955264,5983936,6003088,6174630,6197724,6324318,6351840,6429600

%N Nonsquares which in at least two ways are the product of two numbers with the same digits (leading zeros are forbidden).

%C Subsequence of A072443.

%e 101556 = 156*651 = 273*372; 2096640 = 1092*1920 = 1365*1536.

%o (PARI) {for(n=100,6500000,k=floor(log(n)/log(100)); f=divisors(n); v=[]; for(h=1,matsize(f)[2],if(10^k<f[h]&& f[h]<10^(k+1),v=concat(v,f[h]))); b=matsize(v)[2]; if(b>1, w=[]; for(i=1,b,s=[]; a=v[i]; while(a>0, d=divrem(a,10); a=d[1]; s=concat(d[2],s)); w=concat(w,[vecsort(s)])); c=0; for(i=1,b-1, for(j=i+1,b, if(c<2&&w[i]==w[j],if(v[i]*v[j]==n,if(c==1,print1(n,","); c=2,c=1)))))))}

%Y Cf. A072443.

%K base,nonn

%O 0,1

%A _Klaus Brockhaus_, Nov 14 2002

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Last modified November 25 08:38 EST 2020. Contains 338623 sequences. (Running on oeis4.)