login
A044070
Numbers n such that string 2,1 occurs in the base 4 representation of n but not of n-1.
0
9, 25, 36, 41, 57, 73, 89, 100, 105, 121, 137, 144, 164, 169, 185, 201, 217, 228, 233, 249, 265, 281, 292, 297, 313, 329, 345, 356, 361, 377, 393, 400, 420, 425, 441, 457, 473, 484, 489, 505, 521, 537, 548, 553, 569, 576, 649
OFFSET
1,1
CROSSREFS
Sequence in context: A305755 A090333 A137190 * A376217 A372724 A348234
KEYWORD
nonn,base
STATUS
approved