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A249436
Integers n such that n/2 < A249151(n) < n.
4
11, 29, 44, 55, 59, 69, 71, 111, 119, 125, 139, 188, 215, 223, 230, 233, 239, 251, 324, 335, 349, 351, 447, 458, 474, 479, 493, 494, 503, 509, 560, 593, 599, 647, 662, 701, 714, 719, 831, 835, 849, 895, 956, 959, 979, 991, 1000, 1007, 1019, 1034, 1063, 1077, 1169, 1224, 1319, 1322, 1364, 1376, 1424, 1427, 1448, 1507
OFFSET
1,1
COMMENTS
Integers n such that A001142(n) [product of elements on row n of Pascal's triangle] is divisible by floor[(n+1)/2]! but not by n!
These are the abscissas of "stray points" in the sparsely populated region between the two topmost rays visible in the scatter plot of A249151 which have slopes 1 and 1/2: A249434 (A006093) and A249424.
LINKS
PROG
(Scheme, with Antti Karttunen's IntSeq-library, two alternative definitions)
(define A249436 (MATCHING-POS 1 0 (lambda (n) (and (> (A249151 n) (/ n 2)) (< (A249151 n) n)))))
(define A249436 (MATCHING-POS 1 0 (lambda (n) (and (zero? (modulo (A001142 n) (A000142 (floor->exact (/ (+ n 1) 2))))) (not (zero? (modulo (A001142 n) (A000142 n))))))))
CROSSREFS
A249437 gives the corresponding values at those points.
Subsequence of A249433.
Sequence in context: A155188 A045469 A219790 * A167521 A031338 A301621
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 02 2014
STATUS
approved