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A356184
Triangle read by rows: n-th row gives the indices of the n repunits that divide A340549(n).
1
1, 1, 2, 1, 2, 4, 1, 2, 3, 6, 1, 2, 3, 4, 6, 1, 2, 3, 4, 6, 12, 1, 2, 3, 4, 6, 8, 12, 1, 2, 3, 4, 5, 6, 10, 12, 1, 2, 3, 4, 5, 6, 8, 10, 12, 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 18, 20, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 18, 20, 24
OFFSET
1,3
EXAMPLE
Triangle begins:
1;
1, 2;
1, 2, 4;
1, 2, 3, 6;
1, 2, 3, 4, 6;
1, 2, 3, 4, 6, 12;
1, 2, 3, 4, 6, 8, 12;
1, 2, 3, 4, 5, 6, 10, 12;
1, 2, 3, 4, 5, 6, 8, 10, 12;
1, 2, 3, 4, 5, 6, 8, 9, 10, 12;
1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 18;
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14;
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 18;
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 18;
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 18, 20;
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 18, 20, 24;
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 24;
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 20, 24, 30;
...
The 5th row is {1, 2, 3, 4, 6} since A340549(5) = 11222211 is the least integer that is divisible by five repunits and these are R_1, R_2, R_3, R_4 and R_6.
CROSSREFS
KEYWORD
nonn,base,tabl
AUTHOR
Bernard Schott, Jul 28 2022
STATUS
approved