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A220249
Numbers of rows R of the Wythoff array such that R is the n-th multiple of a tail of the Lucas sequence.
4
2, 9, 13, 45, 56, 67, 78, 89, 262, 291, 320, 349, 378, 407, 436, 465, 494, 523, 552, 581, 610, 1673, 1749, 1825, 1901, 1977, 2053, 2129, 2205, 2281, 2357, 2433, 2509, 2585, 2661, 2737, 2813, 2889, 2965, 3041, 3117, 3193, 3269, 3345, 3421, 3497, 3573, 3649
OFFSET
1,1
COMMENTS
This sequence is corresponding to A173027. Also Row 2 of the array A173028.
It appears that the numbers of this sequence form groups of m members respectively with same distance d of two consecutive values a(n) such that d is equal to odd-indexed Lucas numbers (A002878) while m is equal to odd-indexed Fibonacci numbers (A001519). Example: from n=988 to 2584 d=3571 and m=1597;
Also of interest are the gaps between two consecutive groups which appear to be sums of one Lucas number L(2n+1) plus one Fibonacci number F(4n). Example: gap 5 after a(55) is 6964 = L(11) + F(20) = 199 + 6765
Likewise, the tail (as mentioned in this sequence's name) of the Lucas sequence is chopped off by two initial terms at each of the gap positions.
EXAMPLE
Referring to rows of the Wythoff array (A035513),
Row 2: (4,7,11,18,...) = 1*(4,7,11,18,29,47,76,...)
Row 9: (22,36,58,...) = 2*(11,18,29,47,76...)
Row 13: (33,54,87,...) = 3*(11,18,29,47,76...)
Row 45: (116,188,304,...) = 4*(29,47,76...)
CROSSREFS
KEYWORD
nonn
AUTHOR
K. G. Stier, Dec 08 2012
STATUS
approved