A088673 a(n) = n mod A002024(n), where A002024 is "n appears n times": 1, 2, 2, 3, 3, 3, ...

0, 0, 1, 1, 2, 0, 3, 0, 1, 2, 1, 2, 3, 4, 0, 4, 5, 0, 1, 2, 3, 1, 2, 3, 4, 5, 6, 0, 5, 6, 7, 0, 1, 2, 3, 4, 1, 2, 3, 4, 5, 6, 7, 8, 0, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 0, 7, 8, 9, 10, 11, 0, 1, 2, 3, 4, 5, 6, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 0, 8, 9, 10, 11, 12, 13, 0, 1, 2

Offset

1,5

Links

Table of n, a(n) for n=1..100.

Example

a(7) = 3: A002024(7) = 4 and 7 mod 4 = 3.

Mathematica

Table[Mod[n, Floor[1/2+Sqrt[2n]]], {n, 100}] (* Harvey P. Dale, Feb 09 2013 *)

Prog

(Python)
from math import isqrt
def A088673(n): return n%((m:=isqrt(k:=n<<1))+(k>m*(m+1))) # Chai Wah Wu, Nov 07 2024

Crossrefs

Cf. A002024.

Sequence in context: A160271 A274912 A065134 * A339662 A336316 A362110

Adjacent sequences: A088670 A088671 A088672 * A088674 A088675 A088676

Keyword

nonn,easy

Author

Gary W. Adamson, Oct 04 2003

Extensions

Corrected and extended by Ray Chandler, Oct 04 2003

Corrected offset by Chai Wah Wu, Nov 07 2024

Status

approved