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A369243
a(n) is the least integer k whose arithmetic derivative is equal to the n-th partial sum of primorials, and 0 if no such k exists.
5
2, 0, 14, 45, 198, 5114, 65174, 1086194, 20485574, 465779078, 0, 293420849770, 318745032938881, 256934628877545, 26789279193702134
OFFSET
0,1
COMMENTS
a(n) = the smallest integer k for which A003415(k) = A143293(n), and 0 if no such k exists.
FORMULA
a(n) <= A369244(n).
a(n) = A369240(n,1) if A369239(n) > 0; otherwise a(n) = 0. - Max Alekseyev, Sep 17 2025
EXAMPLE
a(0) = 2 as the least number k such that A003415(k) = A143293(0) = 1 is 2.
a(1) = 0 as there is no number k such that A003415(k) = A143293(1) = 3.
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Antti Karttunen, Jan 19 2024
EXTENSIONS
a(13)-a(14) from Max Alekseyev, Oct 11 2025
STATUS
approved