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A225254
Number of distinct values of the sum of 3 products of two 0..n integers.
3
1, 4, 12, 25, 43, 67, 95, 130, 169, 215, 267, 324, 385, 454, 527, 606, 692, 784, 880, 983, 1090, 1205, 1325, 1449, 1578, 1716, 1860, 2008, 2162, 2323, 2488, 2661, 2838, 3022, 3210, 3403, 3605, 3813, 4025, 4242, 4464, 4695, 4930, 5173, 5420, 5673, 5933, 6197
OFFSET
0,2
LINKS
PROG
(Python)
from itertools import combinations_with_replacement
def A225254(n): return len({sum(x) for x in combinations_with_replacement({i*j for i in range(n+1) for j in range(i+1)}, 3)}) # Chai Wah Wu, Oct 13 2023
CROSSREFS
Row 3 of A225252.
Sequence in context: A008080 A008157 A116668 * A008186 A008264 A000297
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 04 2013
EXTENSIONS
a(0)=1 prepended by Alois P. Heinz, Oct 13 2023
STATUS
approved