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A100384
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a(n) = the smallest number x >= 2 such that for m = x to x + n - 1, A006530(m) increases.
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5
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2, 2, 8, 8, 90, 168, 9352, 46189, 721970, 721970, 6449639, 565062156, 11336460025, 37151747513, 256994754033
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OFFSET
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1,1
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COMMENTS
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A006530(m) is the largest prime factor of m.
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LINKS
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EXAMPLE
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a(5)=90 because the largest prime factors of 90,91,92,93,94 are 5,13,23,31,47.
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PROG
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(Python)
from sympy import factorint
k, a = 2, [max(factorint(m+2)) for m in range(n)]
while True:
for i in range(1, n):
if a[i-1] >= a[i]:
break
else:
return k
a = a[i:] + [max(factorint(k+j+n)) for j in range(i)]
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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