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A014631 Numbers in order in which they appear in Pascal's triangle. 8
1, 2, 3, 4, 6, 5, 10, 15, 20, 7, 21, 35, 8, 28, 56, 70, 9, 36, 84, 126, 45, 120, 210, 252, 11, 55, 165, 330, 462, 12, 66, 220, 495, 792, 924, 13, 78, 286, 715, 1287, 1716, 14, 91, 364, 1001, 2002, 3003, 3432, 105, 455, 1365, 5005, 6435, 16, 560, 1820, 4368, 8008, 11440 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A permutation of the natural numbers. - Robert G. Wilson v, Jun 12 2014

In Pascal's triangle a(n) occurs the first time in row A265912(n). - Reinhard Zumkeller, Dec 18 2015

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Dana G. Korssjoen, Biyao Li, Stefan Steinerberger, Raghavendra Tripathi, and Ruimin Zhang, Finding structure in sequences of real numbers via graph theory: a problem list, arXiv:2012.04625, Dec 08, 2020

F. Richman, Combinations and Permutations

Index entries for triangles and arrays related to Pascal's triangle

Index entries for sequences that are permutations of the natural numbers

MATHEMATICA

lst = {1}; t = Flatten[Table[Binomial[n, m], {n, 16}, {m, Floor[n/2]}]]; Do[ If[ !MemberQ[lst, t[[n]]], AppendTo[lst, t[[n]] ]], {n, Length@t}]; lst (* Robert G. Wilson v *)

DeleteDuplicates[Flatten[Table[Binomial[n, m], {n, 20}, {m, 0, Floor[n/2]}]]] (* Harvey P. Dale, Apr 08 2013 *)

PROG

(Haskell)

import Data.List (nub)

a014631 n = a014631_list !! (n-1)

a014631_list = 1 : (nub $ concatMap tail a034868_tabf)

-- Reinhard Zumkeller, Dec 19 2015

CROSSREFS

Cf. A034356, A074909, A119629.

Cf. A034868, A119629 (inverse), A265912.

Sequence in context: A257798 A183079 A119629 * A263266 A263268 A257472

Adjacent sequences:  A014628 A014629 A014630 * A014632 A014633 A014634

KEYWORD

nonn,easy

AUTHOR

Mohammad K. Azarian

EXTENSIONS

More terms from Erich Friedman

Offset changed by Reinhard Zumkeller, Dec 18 2015

STATUS

approved

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Last modified January 20 17:22 EST 2021. Contains 340303 sequences. (Running on oeis4.)