OFFSET
1,2
COMMENTS
Johnson square pyramid: a square base with four equilateral triangle- faces. It is placed upright on top of the cube. All the edge lengths are equal.
LINKS
Georg Fischer, Table of n, a(n) for n = 1..1000 [first 203 terms from K. D. Bajpai]
Wikipedia, Square pyramid
EXAMPLE
a(4) = 79: volume = sqrt(2)/6*k^3 + k^3 = sqrt(2)/6*4^3 + 4^3 = 79.0849... and floor(79.0849...) = 79.
MAPLE
a:= n-> floor((sqrt(2)/6 + 1)*n^3):
seq(a(n), n=1..43);
CROSSREFS
KEYWORD
nonn
AUTHOR
K. D. Bajpai, Sep 19 2013
STATUS
approved