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Antti Karttunen, Table of n, a(n) for n = 1..10000
Index entries for sequences related to lcm's
Index entries for sequences computed from indices in prime factorization
a(1) = 1; for n > 1, a(n) = lcm(A055396(n), a(A028234(n)).
Other identities. For all n >= 1:
a(A007947(n)) = a(n).
a(A181819(n)) = A072411(n).
Here primepi (A000720) gives the index of its prime argument:
n = 14 = 2 * 7, thus a(14) = lcm(primepi(2), primepi(7)) = lcm(1,4) = 4.
n = 21 = 3 * 7, thus a(21) = lcm(primepi(3), primepi(7)) = lcm(2,4) = 4.
Table[Apply[LCM, PrimePi[FactorInteger[n][[All, 1]] ]] + Boole[n == 1], {n, 105}] (* Michael De Vlieger, Aug 14 2017 *)
(Scheme) (define (A290103 n) (if (= 1 n) n (lcm (A055396 n) (A290103 (A028234 n))))) ;; Antti Karttunen, Aug 13 2017
Cf. A000040, A000720, A003963, A007947, A156061, A290104, A290105.
Cf. also A072411, A181819.
Sequence in context: A108230 A253558 A061395 * A156061 A225395 A295877
Adjacent sequences: A290100 A290101 A290102 * A290104 A290105 A290106
nonn
Antti Karttunen, Aug 13 2017
approved