A388065 - OEIS

A388065

Irregular triangle T(n,k) read by rows in which row n lists, in nonincreasing order, the areas of the faces of the stepped pyramid with n levels described in A245092, n >= 1, k >= 1.

1, 1, 1, 1, 1, 1, 4, 3, 3, 3, 2, 2, 1, 1, 1, 8, 6, 6, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 15, 10, 10, 7, 3, 3, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 21, 15, 15, 7, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 33, 21, 21, 12, 7, 4, 4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1

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OFFSET

1,7

COMMENTS

The "stepped pyramid with n levels" is a polyhedron that has A325300(n) faces, A325301(n) edges, A325302(n) vertices and whose volume is A175254(n) and whose surface area is A328366(n). The area of its base is A024916(n).

The sequence is infinite.

LINKS

Table of n, a(n) for n=1..105.

Omar E. Pol, Illustration of initial terms (rows: 1..5)

EXAMPLE

Triangle begins:

1, 1, 1, 1, 1, 1;

4, 3, 3, 3, 2, 2, 1, 1, 1;

8, 6, 6, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1;

15, 10, 10, 7, 3, 3, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1;

21, 15, 15, 7, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1;

33, 21, 21, 12, 7, 4, 4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1;