A299986 Lexicographic first sequence of nonnegative integers such that a(n) + a(n+1) has a digit 6, and no term occurs twice.

0, 6, 10, 16, 20, 26, 30, 31, 5, 1, 15, 11, 25, 21, 35, 27, 9, 7, 19, 17, 29, 32, 4, 2, 14, 12, 24, 22, 34, 28, 8, 18, 38, 23, 3, 13, 33, 36, 40, 46, 50, 56, 60, 66, 70, 76, 80, 81, 45, 41, 55, 51, 65, 61, 75, 71, 85, 77, 39, 37, 49, 47, 59, 57, 69, 67, 79, 82, 44, 42, 54, 52, 64, 62, 74, 72, 84, 78, 48, 58, 68, 88, 73, 43, 53, 63, 83, 86, 90, 96, 100

Offset: 0

Author

M. F. Hasler and Eric Angelini, Feb 22 2018

Keywords

• nonn
• base

Comments

A permutation of the nonnegative integers.

Crossrefs

Cf. A299976 (analog with positive terms), A299957 (analog with digit 1), A299970, A299982..A299988, A299969 (digit 0, 2..8, 9).

Programs

PARI

a(n,f=1,d=6,a=0,u=[a])={for(n=1,n,f&&if(f==1,print1(a","),write(f,n-1," "a));for(k=u[1]+1,oo,setsearch(u,k)&&next;setsearch(Set(digits(a+k)),d)&&(a=k)&&break);u=setunion(u,[a]);u[2]==u[1]+1&&u=u[^1]);a}