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.

A014770 Squares of even pentagonal numbers.

Original entry on oeis.org

0, 144, 484, 4900, 8464, 30976, 44100, 108900, 141376, 283024, 348100, 611524, 725904, 1166400, 1350244, 2033476, 2310400, 3312400, 3709476, 5116644, 5664400, 7573504, 8305924, 10824100, 11778624, 15023376, 16240900, 20340100
Offset: 0

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Keywords

Crossrefs

Cf. A014633.
Even terms of A100255.

Formula

a(n) = A014633(n)^2. - Sean A. Irvine, Nov 20 2018
From Chai Wah Wu, Jan 23 2020: (Start)
a(n) = a(n-1) + 4*a(n-2) - 4*a(n-3) - 6*a(n-4) + 6*a(n-5) + 4*a(n-6) - 4*a(n-7) - a(n-8) + a(n-9) for n > 8.
G.f.: -4*x*(x^7 + 168*x^6 + 227*x^5 + 1428*x^4 + 551*x^3 + 960*x^2 + 85*x + 36)/((x - 1)^5*(x + 1)^4). (End)

Extensions

More terms from Erich Friedman.
a(0)=0 inserted for consistency with A014633 by Sean A. Irvine, Nov 20 2018