A260060 Least number such that exactly n iterations of A034690 are required to reach one of the fixed points, 1 or 15.
1, 8, 7, 4, 3, 2, 19, 12, 6, 5, 13, 9, 10, 16, 30, 18, 34, 36, 66, 162, 924, 71820
Offset: 0
Examples
The orbits are: {1}, {8, 15}, {7, 8, 15}, {4, 7, 8, 15}, {3, 4, 7, 8, 15}, {2, 3, 4, 7, 8, 15}, {19, 11, 3, 4, 7, 8, 15}, {12, 19, 11, 3, 4, 7, 8, 15}, {6, 12, 19, 11, 3, 4, 7, 8, 15}, {5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {10, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {16, 22, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {30, 27, 22, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {18, 30, 27, 22, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {34, 18, 30, 27, 22, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {36, 46, 18, 30, 27, 22, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {66, 36, 46, 18, 30, 27, 22, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {162, 66, 36, 46, 18, 30, 27, 22, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {924, 168, 102, 36, 46, 18, 30, 27, 22, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}, {71820, 1104, 168, 102, 36, 46, 18, 30, 27, 22, 9, 13, 5, 6, 12, 19, 11, 3, 4, 7, 8, 15}
Links
- E. Angelini et al., List the dividers, sum the digits, SeqFan list, Nov. 2015 [Broken link]
- Eric Angelini et al., List the dividers [sic], sum the digits, lost messages reconstructed by _N. J. A. Sloane_, Dec 21 2024
Programs
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PARI
a(n)=for(k=1,9e9, A086793(k)==n&&return(k))
Comments