A225259 Number of distinct values of the sum of 2 products of three 0..n integers

3, 12, 36, 75, 157, 254, 434, 635, 911, 1237, 1734, 2162, 2908, 3611, 4461, 5435, 6734, 7879, 9568, 10964, 12861, 14913, 17438, 19426, 22381, 25251, 28482, 31624, 35879, 39100, 44165, 48267, 53463, 58590, 64476, 69214, 76693, 83132, 90303, 96766

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..139

Prog

(Python)
def a(n):
  zn = list(range(n+1))
  prod3 = list(set(i*j*k for i in zn for j in zn[i:] for k in zn[j:]))
  return len(set(a+b for i, a in enumerate(prod3) for b in prod3[i:]))
print([a(n) for n in range(1, 42)]) # Michael S. Branicky, Mar 12 2021

Crossrefs

Row 2 of A225258.

Sequence in context: A009787 A135190 A101069 * A334891 A242526 A167667

Adjacent sequences: A225256 A225257 A225258 * A225260 A225261 A225262

Keyword

nonn

Author

R. H. Hardin, May 04 2013

Status

approved