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A225259 Number of distinct values of the sum of 2 products of three 0..n integers 1
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified August 5 07:54 EDT 2021. Contains 346464 sequences. (Running on oeis4.)