A242399 Write n and 3n in ternary representation and add all trits modulo 3.

0, 4, 8, 12, 16, 11, 24, 19, 23, 36, 40, 44, 48, 52, 47, 33, 28, 32, 72, 76, 80, 57, 61, 56, 69, 64, 68, 108, 112, 116, 120, 124, 119, 132, 127, 131, 144, 148, 152, 156, 160, 155, 141, 136, 140, 99, 103, 107, 84, 88, 83, 96, 91, 95, 216, 220, 224, 228, 232

Offset: 0

Author

Reinhard Zumkeller, May 13 2014

Keywords

• nonn
• base

Examples

			n = 25, 3*n = 75:
.  A007089(25) =  221
.  A007089(75) = 2210
.   add trits    ----
.    modulo 3    2101 = A007089(64), hence a(25) = 64.
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 0..10000
• P. Mathonet, M. Rigo, M. Stipulanti and N. Zénaïdi, On digital sequences associated with Pascal's triangle, arXiv:2201.06636 [math.NT], 2022.
• Eric Weisstein's World of Mathematics, Ternary.
• Wikipedia, Ternary numeral system
• Index entries for sequences related to carryless arithmetic

Crossrefs

Cf. A004488, A007089, A008586, A030341, A048724, A242400, A242407.

Row / column 4 of A325820.

Programs

Haskell

a242399 n = foldr (\t v -> 3 * v + t) 0 $
                  map (flip mod 3) $ zipWith (+) ([0] ++ ts) (ts ++ [0])
            where ts = a030341_row n

Formula

a(n) <= 4*n; a(m) = 4*m iff m is a term of A242407.

a(n) = A008586(n) - A242400(n).