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A104025 Least number k that can be written as k^2 * j with 0 < j <= k and gcd(k, j) = 1 in n ways. 1
2, 1, 100, 900, 44100, 108900, 1232100, 11492100, 5336100, 12744900, 97416900 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
LINKS
MATHEMATICA
t = Sort[ Flatten[ Table[n = k^2*j; If[ GCD[k, j] == 1 && 10^5 < n < 10^8, n, {}], {k, 15000}, {j, k}]]]; l = Length[t]; t[[Select[ Range[l - 11], t[[ # ]] == t[[ # + 9]] &]]]
CROSSREFS
Sequence in context: A141527 A301631 A191298 * A335600 A039923 A081708
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified June 20 09:33 EDT 2024. Contains 373515 sequences. (Running on oeis4.)