OFFSET
1,2
COMMENTS
Complement of A005823.
Integers m such that central Delannoy number A001850(m) == 0 (mod 3). - Emeric Deutsch and Bruce E. Sagan, Dec 04 2003
Integers m such that A026375(m) == 0 (mod 3). - Fabio Visonà, Aug 03 2023
LINKS
Johann Cigler, Some elementary observations on Narayana polynomials and related topics, arXiv:1611.05252 [math.CO], 2016. See p.25.
Mathematics Stack Exchange, Proof that integers m in this sequence are such that A026375(m) == 0 (mod 3).
MATHEMATICA
Select[Range[100], DigitCount[#, 3, 1]>0&] (* Harvey P. Dale, Nov 26 2022 *)
PROG
(Python)
from itertools import count, islice
def A081606_gen(): # generator of terms
a = 0
for n in count(1):
b = int(bin(n)[2:], 3)<<1
yield from range(a+1, b)
a = b
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Mar 23 2003
EXTENSIONS
More terms from Emeric Deutsch and Bruce E. Sagan, Dec 04 2003
STATUS
approved