A189036 a(n)= lcm(n,n')/gcd(n,n'), where n' is the arithmetic derivative of n.

0, 2, 3, 1, 5, 30, 7, 6, 6, 70, 11, 12, 13, 126, 120, 2, 17, 42, 19, 30, 210, 286, 23, 66, 10, 390, 1, 56, 29, 930, 31, 10, 462, 646, 420, 15, 37, 798, 624, 170, 41, 1722, 43, 132, 195, 1150, 47, 21, 14, 90, 1020, 182, 53, 6, 880, 322, 1254, 1798, 59, 345, 61, 2046, 357, 3, 1170, 4026, 67, 306, 1794, 4130, 71, 78, 73, 2886, 165, 380, 1386, 5538, 79, 55, 12, 3526, 83, 651, 1870, 3870, 2784, 770, 89, 1230, 1820, 552, 3162, 4606, 2280, 102, 97, 154, 825, 35

Offset

1,2

Comments

Least common multiple of n and its arithmetic derivative divided by greatest common divisor of n and its arithmetic derivative.

Links

Table of n, a(n) for n=1..100.

Formula

a(n) = lcm(n,n')/gcd(n,n') = A086130(n)/A085731(n).

Example

n = 8, n'= 12,  lcm(8,12)= 24, gcd(8,12)= 4, hence a(8)=24/4 = 6.

Crossrefs

Cf. A003415, A085731, A086130, A083345, A083346.

Sequence in context: A182822 A137211 A212275 * A319952 A174665 A256470

Adjacent sequences: A189033 A189034 A189035 * A189037 A189038 A189039

Keyword

nonn

Author

Giorgio Balzarotti, Apr 15 2011

Status

approved