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A214848 First difference of A022846. 5
1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Number of triangular numbers in interval [n^2, (n+1)^2).

For n > 0: a(n) = A006338(n). - Reinhard Zumkeller, Mar 03 2014

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

EXAMPLE

28 is in [25, 36), a(5) = 1.

36 and 45 are in [36, 49), a(6) = 2.

MATHEMATICA

Differences[Round[Sqrt[2]Range[0, 100]]] (* Harvey P. Dale, Jun 14 2020 *)

PROG

(Haskell)

a214848 n = a214848_list !! n

a214848_list = zipWith (-) (tail a022846_list) a022846_list

-- Reinhard Zumkeller, Mar 03 2014

CROSSREFS

Cf. A022846.

Sequence in context: A175922 A214856 A006337 * A006338 A020903 A133083

Adjacent sequences:  A214845 A214846 A214847 * A214849 A214850 A214851

KEYWORD

nonn,easy

AUTHOR

Philippe Deléham, Mar 08 2013

STATUS

approved

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Last modified June 15 18:11 EDT 2021. Contains 345049 sequences. (Running on oeis4.)