|
| |
|
|
A101369
|
|
a(2n-1) = the smallest positive integer not occurring earlier in the sequence. a(2n) = the a(2n-1)th smallest positive integer among those not occurring earlier in the sequence.
|
|
1
| |
|
|
1, 2, 3, 6, 4, 9, 5, 12, 7, 16, 8, 19, 10, 23, 11, 26, 13, 30, 14, 33, 15, 36, 17, 40, 18, 43, 20, 47, 21, 50, 22, 53, 24, 57, 25, 60, 27, 64, 28, 67, 29, 70, 31, 74, 32, 77, 34, 81, 35, 84, 37, 88, 38, 91, 39, 94, 41, 98, 42, 101, 44, 105, 45, 108, 46, 111, 48, 115, 49, 118
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
COMMENTS
| A permutation of the positive integers.
|
|
|
FORMULA
| a(n)<a(n+2). - Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 11 2005
For n>0, a(2n-1)=1+floor((2n-1)/sqrt(2)) and a(2n)=2n+floor((2n)/sqrt(2)-1/sqrt(2)) - Benoit Cloitre (benoit7848c(AT)orange.fr), Feb 22 2005
|
|
|
MATHEMATICA
| lst = Range[150]; a[n_] := a[n] = If[ OddQ[n], b = First[lst]; lst = Rest[lst]; b, b = lst[[ a[n - 1]]]; lst = Drop[lst, {a[n - 1]}]; b]; Table[ a[n], {n, 70}]
|
|
|
CROSSREFS
| Sequence in context: A059900 A123664 A084980 * A125147 A103864 A152679
Adjacent sequences: A101366 A101367 A101368 * A101370 A101371 A101372
|
|
|
KEYWORD
| nonn,nice
|
|
|
AUTHOR
| Leroy Quet Jan 13 2005
|
|
|
EXTENSIONS
| More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 11 2005
|
| |
|
|
