login
A363420
Let D be the largest digit of a(n) + a(n+1). The successive Ds reproduce the successive digits of the sequence. By construction, we do not accept any zero in the sequence. This is the lexicographically earliest sequence of distinct terms > 0 with this property.
0
1, 9, 81, 2, 8, 4, 14, 26, 74, 66, 36, 24, 3, 11, 5, 21, 12, 34, 68, 46, 57, 43, 58, 47, 55, 45, 56, 64, 39, 65, 41, 7, 17, 19, 6, 31, 13, 18, 27, 51, 53, 22, 23, 28, 15, 35, 16, 44, 62, 42, 61, 29, 32, 73, 67, 33, 37, 63, 54, 946, 25, 38, 75, 925, 76, 127, 873
OFFSET
1,2
LINKS
Eric Angelini, Échecs et Maths, Personal blog, bottom of page.
EXAMPLE
The largest digit of the sum 1 + 9 = 10 is 1
the largest digit of the sum 9 + 81 = 90 is 9
the largest digit of the sum 81 + 2 = 83 is 8
the largest digit of the sum 2 + 8 = 10 is 1
the largest digit of the sum 8 + 4 = 12 is 2
the largest digit of the sum 4 + 14 = 18 is 8, etc.
We see that the last column reproduces the successive digits of the sequence.
MATHEMATICA
a[1]=1; a[n_]:=a[n]=(k=1; While[Max[s=IntegerDigits[k+a[n-1]]] !=Flatten[IntegerDigits/@Array[a, n-1]][[n-1]] ||MemberQ[IntegerDigits[k], 0] ||MemberQ[Array[a, n-1], k], k++]; k); Array[a, 67] (* Giorgos Kalogeropoulos, Jul 11 2023 *)
CROSSREFS
Cf. A332803.
Sequence in context: A055070 A143848 A317052 * A352386 A332702 A117817
KEYWORD
base,nonn
AUTHOR
Eric Angelini, Jul 03 2023
STATUS
approved