A253808 a(n) = A106291(n)/(modified A223486(n)), n >= 1.

1, 1, 4, 2, -4, 4, 4, -12, 4, -12, 2, -24, -28, 4, -8, -24, -36, 4, 2, -12, -16, 2, 4, -24, -20, -84, 4, -48, 2, -24, 2, -48, -40, -36, -16, -24, -76, 2, -56, -12, 4, -48, 4, 2, -24, 4, 4, -24, 4, -60, -72, -84, -108, 4, -20, -48, -72, 2, 2, -24, -60, 2, -48, -96, -28, -120, 4, -36

Offset: 1

Author

Wolfdieter Lang, Jan 20 2015

Keywords

• sign
• easy

Comments

This sequence uses A223486 with the first two entries 1, 3, as obtained when one considers the Lucas numbers A000204 for n >= 1 (not A000032 for n >= 0).

Crossrefs

Cf. A106291, A223486, A001176 (Fibonacci case).

Formula

a(n) = A106291(n)/(modified A223486(n)), n >= 1, where one uses A223486(1) = 1 and A223486(2) = 3.