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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 (list; table; graph; refs; listen; history; text; internal format)
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.
LINKS
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

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Last modified August 29 09:09 EDT 2024. Contains 375511 sequences. (Running on oeis4.)