cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A201125 Differences between odd powers of 2 and the next smaller square.

Original entry on oeis.org

1, 4, 7, 7, 28, 23, 92, 7, 28, 112, 448, 1792, 7168, 5503, 22012, 88048, 166831, 296599, 444943, 296863, 1187452, 4749808, 7135951, 4817239, 19268956, 77075824, 118490767, 94338007, 377352028, 1509408112, 3000631951, 5928526807, 11566105231, 21968416927, 39281659711, 59942622847, 45402459391, 181609837564, 726439350256
Offset: 1

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Author

Hugo Pfoertner, Nov 27 2011

Keywords

Examples

			a(1)=2^1-1^1=1, a(2)=2^3-2^2=4, a(3)=2^5-5^2=32-25=7
		

Crossrefs

Programs

  • Mathematica
    Table[2^n-Floor[Sqrt[2^n]]^2,{n,1,81,2}] (* Harvey P. Dale, Feb 25 2018 *)

Formula

a(n) = 2^(2*n-1) - floor(sqrt(2^(2*n-1)))^2.
Apparently a(n) = A095803(n)/4 for n >= 1. - Hugo Pfoertner, Dec 07 2022