A038557 Periodic derivative of n in base 3.

0, 2, 1, 4, 8, 0, 8, 0, 4, 10, 14, 15, 22, 26, 18, 7, 2, 3, 20, 21, 25, 5, 6, 1, 17, 9, 13, 28, 32, 33, 40, 44, 36, 52, 47, 48, 64, 68, 69, 76, 80, 72, 61, 56, 57, 19, 23, 24, 4, 8, 0, 16, 11, 12, 56, 57, 61, 68, 69, 64, 80, 72, 76, 11, 12, 16, 23, 24, 19, 8, 0, 4, 47, 48, 52, 32

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• nice
• easy

Examples

			14=112->200 so a(14)=18.
		

References

• Simmons, G. J. The structure of the differentiation digraphs of binary sequences. Ars Combin. 35 (1993), A, 71-88. Math. Rev. 95f:05052.

Crossrefs

Cf. A038554-A038556.

Formula

If n=b_k b_{k-1} ... b_0 in base 3, a(n) is number with ternary expansion (b_k+b_{k-1}) (b_{k-1}+b_{k-2}) ... (b_1+b_0) (b_0+b_{k}).

Extensions

Corrected and extended by Naohiro Nomoto, Apr 08 2001