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A074625
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Triangular array T(n,k) (n >= 1, 1 <= k <= n) read by rows, where T(n,k) = smallest number x such that Mod[sigma[x],n]=k.
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1
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1, 1, 3, 1, 7, 2, 1, 5, 2, 3, 1, 4, 2, 3, 8, 1, 7, 2, 3, 2401, 5, 1, 29, 2, 3, 6, 5, 4, 1, 10, 2, 3, 9, 5, 4, 7, 1, 19, 2, 3, 13, 5, 4, 7, 10, 1, 6, 2, 3, 8, 5, 4, 7, 18, 19, 1, 9, 2, 3, 24, 5, 4, 7, 16, 21, 43, 1, 13, 2, 3, 2401, 5, 4, 7, 49, 31213, 9604, 6, 1, 8, 2, 3, 10, 5, 4, 7, 33, 22
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 1,3
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FORMULA
| Min{x; Mod[sigma[x], n]=r}, r=1..n, n=1, ...
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EXAMPLE
| 1; 1,3; 1,7,2; 1,5,2,3; 1,4,2,3,8; ...
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MATHEMATICA
| {k=0, s=0, fl=1}; Table[Print["#"]; Table[fl=1; Print[{r, m}]; Do[s=Mod[DivisorSigma[1, n], m]; If[(s==r)&&(fl==1), Print[n]; fl=0], {n, 1, 150000}], {r, 0, m-1}], {m, 1, 25}]
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CROSSREFS
| Cf. A000203, A028982, A074384-A074386, A072461, A072462, A072862.
Sequence in context: A146217 A146007 A061782 * A169659 A091724 A016576
Adjacent sequences: A074622 A074623 A074624 * A074626 A074627 A074628
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KEYWORD
| nonn,tabl
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Aug 26 2002
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