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A098793
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Triangle read by rows, 1<=k<=n: T(n,k) = smallest number having exactly as many divisors as n and k together.
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0
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2, 4, 6, 4, 6, 6, 6, 16, 16, 12, 4, 6, 6, 16, 6, 16, 12, 12, 64, 12, 24, 4, 6, 6, 16, 6, 12, 6, 16, 12, 12, 64, 12, 24, 12, 24, 6, 16, 16, 12, 16, 64, 16, 64, 12, 16, 12, 12, 64, 12, 24, 12, 24, 64, 24, 4, 6, 6, 16, 6, 12, 6, 12, 16, 12, 6, 64, 24, 24, 36, 24, 48, 24, 48, 36, 48, 24, 60, 4
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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Triangle begins:
2
4 6
4 6 6
6 16 16 12
4 6 6 16 6
...
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MATHEMATICA
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A005179 = Cases[Import["https://oeis.org/A005179/b005179.txt", "Table"], {_, _}][[All, 2]];
T[n_, k_] := A005179[[DivisorSigma[0, n] + DivisorSigma[0, k]]];
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PROG
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(PARI) T(n, k) = my(x=numdiv(n)+numdiv(k), y=1); while(numdiv(y)!= x, y++); y; \\ Michel Marcus, Sep 15 2021
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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