

A360806


a(0) = 1; for n >= 1, a(n) is the least integer k > a(n1) such that k / A000005(k) = a(n1).


0




OFFSET

0,2


LINKS



EXAMPLE

a(0) = 1.
a(1) = 2 because the least k > 1 such that k / A000005(k) = 1 is k = 2.
a(2) = 8 because the least k > 2 such that k / A000005(k) = 2 is k = 8.
a(3) = 80 because the least k > 8 such that k / A000005(k) = 8 is k = 80.
and so on.


MATHEMATICA

a[0] = 1; a[n_] := a[n] = Module[{m = a[n  1], k}, k = 2*m; While[k != m*DivisorSigma[0, k], k += m]; k]; Array[a, 9, 0] (* Amiram Eldar, Feb 21 2023 *)


CROSSREFS



KEYWORD

nonn,more


AUTHOR



EXTENSIONS



STATUS

approved



