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A125153
The interspersion T(3,2,1), by antidiagonals.
2
1, 4, 2, 13, 6, 3, 40, 20, 10, 5, 121, 60, 30, 15, 7, 364, 182, 91, 45, 22, 8, 1093, 546, 273, 136, 68, 25, 9, 3280, 1640, 820, 410, 205, 76, 28, 11, 9841, 4920, 2460, 1230, 615, 230, 86, 34, 12, 29524, 14762, 7381, 3690, 1845, 691, 259, 102, 38, 14
OFFSET
1,2
COMMENTS
Every positive integer occurs exactly once and each pair of rows are interspersed after initial terms.
REFERENCES
Clark Kimberling, Interspersions and fractal sequences associated with fractions (c^j)/(d^k), Journal of Integer Sequences 10 (2007, Article 07.5.1) 1-8.
FORMULA
Row 1: t(1,h)=Floor[r*3^(h-1)], where r=(3^1)/(2^1), h=1,2,3,... Row 2: t(2,h)=Floor[r*3^(h-1)], r=(3^2)/(2^2), where 2=Floor[r] is least positive integer (LPI) not in row 1. Row 3: t(3,h)=Floor[r*3^(h-1)], r=(3^3)/(2^3), where 3=Floor[r] is the LPI not in rows 1 and 2. Row m: t(m,h)=Floor[r*3^(h-1)], where r=(3^j)/(2^k), where k is the least integer >=1 for which there is an integer j for which the LPI not in rows 1,2,...,m-1 is Floor[r].
EXAMPLE
Northwest corner:
1 4 13 40 121 364 1093
2 6 20 60 182 546 1640
3 10 30 91 273 820 2460
5 15 45 136 410 1230 3690
7 22 68 205 615 1845 5535
CROSSREFS
Sequence in context: A167557 A069836 A224820 * A191451 A193950 A180194
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Nov 21 2006
STATUS
approved