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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
 101556, 121968, 124012, 133875, 144648, 172900, 185472, 226800, 352170, 433755, 2096640, 3779136, 4264416, 5166504, 5333680, 5448960, 5651919, 5894784, 5955264, 5983936, 6003088, 6174630, 6197724, 6324318, 6351840, 6429600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Subsequence of A072443. LINKS EXAMPLE 101556 = 156*651 = 273*372; 2096640 = 1092*1920 = 1365*1536. PROG (PARI) {for(n=100, 6500000, k=floor(log(n)/log(100)); f=divisors(n); v=[]; for(h=1, matsize(f)[2], if(10^k1, 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)))))))} CROSSREFS Cf. A072443. Sequence in context: A229684 A187642 A023077 * A218170 A153050 A203592 Adjacent sequences:  A077757 A077758 A077759 * A077761 A077762 A077763 KEYWORD base,nonn AUTHOR Klaus Brockhaus, Nov 14 2002 STATUS approved

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Last modified December 4 05:56 EST 2021. Contains 349470 sequences. (Running on oeis4.)