A014799 Squares of odd pentagonal pyramidal numbers.

1, 5625, 164025, 1399489, 6765201, 23532201, 66015625, 159138225, 342731169, 676572121, 1246160601, 2169230625, 3603000625, 5752160649, 8877596841, 13305853201, 19439330625, 27767223225, 38877191929, 53467775361

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Eric Weisstein's World of Mathematics, Pentagonal Pyramidal Number

Formula

From Colin Barker, Apr 17 2012: (Start)

a(n) = (1 + 2*n)^2*(1 + 4*n)^4.

G.f.: (1 + 5618*x + 124671*x^2 + 369404*x^3 + 216463*x^4 + 21042*x^5 + 81*x^6) /(1-x)^7. (End)

a(n) = A015223(n)^2. - R. J. Mathar, Jul 30 2016

Maple

seq( (1+2*n)^2*(1+4*n)^4, n=0..30); # Muniru A Asiru, Oct 09 2017

Mathematica

Table[(1+2*n)^2*(1+4*n)^4, {n, 0, 20}] (* Vincenzo Librandi, Apr 18 2012 *)
Range[0, 20]//(1+2*#)^2*(1+4*#)^4& (* Waldemar Puszkarz, Oct 11 2017 *)

Prog

(Magma) [(1+2*n)^2*(1+4*n)^4: n in [0..30]]; // Vincenzo Librandi, Apr 18 2012
(GAP) A014799:=List(Filtered(List([0..10^2], n->n^2*(n+1)/2), IsOddInt), i->i^2); # Muniru A Asiru, Oct 09 2017

Crossrefs

Cf. A002411, A014800, A015223, A015224.

Sequence in context: A202098 A247261 A203831 * A031573 A031753 A045128

Adjacent sequences: A014796 A014797 A014798 * A014800 A014801 A014802

Keyword

nonn,easy,changed

Author

Mohammad K. Azarian

Status

approved