login
A120230
Split-floor-multiplier sequence (SFMS) using multipliers 1/4 and 4. (SFMS is defined at A120229.)
7
4, 8, 12, 1, 20, 24, 28, 2, 36, 40, 44, 3, 52, 56, 60, 64, 68, 72, 76, 5, 84, 88, 92, 6, 100, 104, 108, 7, 116, 120, 124, 128, 132, 136, 140, 9, 148, 152, 156, 10, 164, 168, 172, 11, 180, 184, 188, 192, 196, 200, 204, 13, 212, 216, 220, 14, 228, 232, 236, 15, 244, 248
OFFSET
1,1
COMMENTS
Self-inverse permutation of the natural numbers.
FORMULA
a(n)=[n/4] if this is positive and new, else a(n)=4n.
EXAMPLE
a(1)=1*4 because [1/4] is not positive.
a(2)=2*4 because [2/4] is not positive.
a(3)=3*4 because [3/4] is not positive.
a(4)=1=[4*(1/4)].
a(5)=5*4 because [5/4]=a(4), not new.
CROSSREFS
Row 4 and column 4 of A059897.
Sequence in context: A109239 A056135 A159586 * A086480 A260249 A277616
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jun 11 2006
STATUS
approved