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A225261
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Number of distinct values of the sum of 4 products of three 0..n integers.
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1
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5, 28, 90, 205, 409, 694, 1123, 1668, 2396, 3298, 4442, 5741, 7410, 9266, 11443, 13937, 16857, 20031, 23746, 27694, 32236, 37143, 42619, 48390, 55021, 62036, 69617, 77815, 86744, 96000, 106372, 117136, 128823, 141110, 154192, 167871, 182867, 198285
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OFFSET
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1,1
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LINKS
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PROG
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(Python)
from itertools import combinations_with_replacement as mc
def a(n):
prods = set(a*b*c for a, b, c in mc(range(n+1), 3))
return len(set(sum(p) for p in mc(prods, 4)))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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