A335795 First differences of A335794.

0, 1, 6, 6, 18, 6, 30, 18, 54, 6, 30, 30, 78, 18, 90, 54, 150, 6, 30, 30, 78, 30, 126, 78, 222, 18, 90, 90, 234, 54, 246, 150, 390, 6, 30, 30, 78, 30, 126, 78, 222, 30, 126, 126, 318, 78, 366, 222, 606, 18, 90, 90, 234, 90, 378, 234, 666, 54, 246, 246, 630, 150, 630, 390, 966, 6, 30, 30, 78, 30, 126, 78, 222, 30, 126, 126, 318

Offset

0,3

Comments

Position of 6 occurs every 2^(n-1) + 1 for n > 0.

Position of 18 appears to occur according to the tetranacci numbers (cf. A000288): 4, 7, 13, 25, 49, ...

References

S. M. Ulam, On some mathematical problems connected with patterns of growth of figures, pp. 215-224 of R. E. Bellman, ed., Mathematical Problems in the Biological Sciences, Proc. Sympos. Applied Math., Vol. 14, Amer. Math. Soc., 1962 (see Example 6, page 224).

Links

Table of n, a(n) for n=0..76.

Example

When written as a triangle:
0
1
6
6 18
6 30 18 54
6 30 30 78 18 90  54 150
6 30 30 78 30 126 78 222 18 90 90 234 54 246 150 390
...

Crossrefs

Cf. A000288, A151723, A335794.

Sequence in context: A038518 A368220 A151724 * A315815 A298026 A315816

Adjacent sequences: A335792 A335793 A335794 * A335796 A335797 A335798

Keyword

nonn

Author

Cody B Duncan, Jun 23 2020

Status

approved