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A230420
Triangle T(n,k) giving the number of terms of A219666 which have n digits (A084558) in their factorial base expansion and whose most significant digit (A099563) in that base is k.
7
1, 1, 1, 2, 2, 1, 6, 5, 4, 4, 22, 19, 16, 14, 12, 94, 82, 73, 65, 59, 55, 479, 432, 395, 362, 336, 314, 293, 2886, 2667, 2482, 2324, 2189, 2073, 1971, 1881, 20276, 19123, 18124, 17249, 16473, 15775, 15140, 14555, 14011, 164224, 156961, 150389, 144378, 138828, 133664, 128831, 124289, 120010, 115974
OFFSET
1,4
COMMENTS
See A007623 for the factorial number system representation.
FORMULA
T(n,k) = 1 + A219652(A230429(n,k)) - A219652(A230428(n,k)).
EXAMPLE
The first rows of this triangular table are:
1;
1, 1;
2, 2, 1;
6, 5, 4, 4;
22, 19, 16, 14, 12;
94, 82, 73, 65, 59, 55;
...
T(4,2) = 5 as only the terms 48, 52, 57, 63 and 70 of A219666 (with factorial base representations 2000, 2020, 2111, 2211 and 2320) have four significant digits in the factorial base, with the most significant digit being 2.
PROG
(Scheme)
(define (A230420 n) (if (<= n 3) 1 (let loop ((i (A230429 n)) (s 0)) (cond ((not (= (A099563 i) (A002260 n))) s) (else (loop (A219651 i) (+ 1 s)))))))
CROSSREFS
Transpose: A230421. Row sums: A219661. Cf. also A230428, A230429, A219652, A219666.
Sequence in context: A125278 A134558 A344639 * A137381 A109316 A162980
KEYWORD
nonn,base,tabl
AUTHOR
Antti Karttunen, Oct 18 2013
STATUS
approved