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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

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 November 12 07:03 EST 2019. Contains 329052 sequences. (Running on oeis4.)