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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 (list; graph; refs; listen; history; text; internal format)
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

Antti Karttunen, Table of n, a(n) for n = 1..115

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.

Cf. A000142, A001142, A249151, A006093, A249424, A249434.

Sequence in context: A155188 A045469 A219790 * A167521 A031338 A301621

Adjacent sequences:  A249433 A249434 A249435 * A249437 A249438 A249439

KEYWORD

nonn

AUTHOR

Antti Karttunen, Nov 02 2014

STATUS

approved

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Last modified July 25 22:38 EDT 2021. Contains 346294 sequences. (Running on oeis4.)