A014770 Squares of even pentagonal numbers.

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

0,2

Links

Table of n, a(n) for n=0..27.

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)

Crossrefs

Cf. A014633.

Even terms of A100255.

Sequence in context: A151820 A322905 A281240 * A131528 A262797 A017402

Adjacent sequences: A014767 A014768 A014769 * A014771 A014772 A014773

Keyword

nonn,easy

Author

Mohammad K. Azarian

Extensions

More terms from Erich Friedman.

a(0)=0 inserted for consistency with A014633 by Sean A. Irvine, Nov 20 2018

Status

approved