A306992 Lexicographically earliest sequence of distinct positive terms such that the product of two consecutive terms is digitally balanced.
1, 2, 5, 7, 6, 25, 9, 15, 10, 17, 12, 13, 4, 3, 14, 11, 18, 31, 19, 29, 8, 23, 26, 22, 40, 63, 33, 69, 36, 67, 34, 21, 99, 27, 30, 82, 28, 81, 35, 61, 16, 47, 50, 53, 48, 73, 37, 20, 41, 56, 45, 49, 43, 52, 51, 42, 54, 46, 55, 44, 57, 38, 65, 127, 66, 135, 70
Offset: 1
Examples
The first terms, alongside the binary representation of a(n)*a(n+1), are: n a(n) bin(a(n)*a(n+1)) -- ---- ---------------- 1 1 10 2 2 1010 3 5 100011 4 7 101010 5 6 10010110 6 25 11100001 7 9 10000111 8 15 10010110 9 10 10101010 10 17 11001100 11 12 10011100 12 13 110100 13 4 1100 14 3 101010 15 14 10011010 16 11 11000110
Links
- Rémy Sigrist, Table of n, a(n) for n = 1..10000
- Rémy Sigrist, PARI program for A306992
Programs
-
PARI
See Links section.
Comments