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A335572
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Irregular triangle whose row n is the set of numbers d+n/d where d is a divisor of n.
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4
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2, 3, 4, 4, 5, 6, 5, 7, 8, 6, 9, 6, 10, 7, 11, 12, 7, 8, 13, 14, 9, 15, 8, 16, 8, 10, 17, 18, 9, 11, 19, 20, 9, 12, 21, 10, 22, 13, 23, 24, 10, 11, 14, 25, 10, 26, 15, 27, 12, 28, 11, 16, 29, 30, 11, 13, 17, 31, 32, 12, 18, 33, 14, 34, 19, 35, 12, 36, 12, 13, 15, 20, 37
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OFFSET
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1,1
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COMMENTS
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The last term of row n is n+1.
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LINKS
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EXAMPLE
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Triangle begins:
[2]
[3]
[4]
[4, 5]
[6]
[5, 7]
[8]
[6, 9]
[6, 10]
[7, 11]
...
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MATHEMATICA
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Table[Map[# + n/# &, #[[-Ceiling[Length[#]/2] ;; -1 ]] ] &@ Divisors[n], {n, 36}] // Flatten (* Michael De Vlieger, Jan 27 2021 *)
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PROG
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(PARI) row(n) = my(d=divisors(n)); Set(vector(#d, k, d[k]+n/d[k]));
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CROSSREFS
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KEYWORD
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nonn,tabf
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AUTHOR
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STATUS
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approved
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