A199971 a(n) = the sum of LCQ_A(n, k) for 1 <= k <= n (see definition in comments).

0, 0, 2, 3, 7, 8, 13, 17, 17, 23, 23, 37, 30, 37, 39, 48, 40, 59, 46, 62, 57, 64, 56, 101, 67, 78, 76, 92, 73, 126, 79, 108, 96, 104, 96, 168, 96, 119, 115, 147

Offset

1,3

Comments

Definition of LCQ_A: The least common non-divisor of type A (LCQ_A) of two positive integers a and b (a<=b) is the least positive non-divisor q of numbers a and b such that 1<=q<=a common to a and b; LCQ_A(a, b) = 0, if no such c exists.

LCQ_A(1, b) = LCQ_A(2, b) = 0 for b >=1. LCQ_A(a, b) = 0 or >= 2.

Links

Table of n, a(n) for n=1..40.

Example

 For n = 6, a(6) = 9 because LCQ_A(6, 1) = 0, LCQ_A(6, 2) = 0, LCQ_A(6, 3) = 0, LCQ_A(6, 4) = 0, LCQ_A(6, 5) = 4, LCQ_A(6, 6) = 4. Sum of results is 8.

Crossrefs

Cf.: A196443 (the sum of GCQ_A(n, k) for 1 <= k <= n).

Cf.: A199972 (the sum of GCQ_B(n, k) for 1 <= k <= n).

Cf.: A199973 (the sum of LCQ_B(n, k) for 1 <= k <= n).

Cf.: A199974 (the sum of LCQ_C(n, k) for 1 <= k <= n).

Sequence in context: A145489 A003307 A105601 * A033082 A084406 A075648

Adjacent sequences: A199968 A199969 A199970 * A199972 A199973 A199974

Keyword

nonn

Author

Jaroslav Krizek, Nov 26 2011

Status

approved