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%I #24 Nov 30 2022 12:39:40
%S 0,1,2,3,4,5,6,7,8,9,0,1,2,1,4,1,6,1,8,1,2,2,2,2,2,2,2,2,2,2,0,3,2,3,
%T 4,3,6,3,8,3,4,4,4,4,4,4,4,4,4,4,0,5,2,5,4,5,6,5,8,5,6,6,6,6,6,6,6,6,
%U 6,6,0,7,2,7,4,7,6,7,8,7,8,8,8,8,8,8,8,8,8,8,0,9,2,9,4,9,6,9,8,9
%N Final digit reached by traveling right (with wraparound) through the digits of n. Each move steps right k places, where k is the digit at the beginning of the move. Moves begin at the most significant digit and d moves are made, where d is the number of digits in n.
%H Moosa Nasir, <a href="https://raw.githubusercontent.com/TealEgg/MoosaNasir/main/Example11323.png">Example of n = 11323</a>.
%e For n = 11323, start at the most significant digit, which is 1.
%e On move 1, travel 1 unit right, reaching the second digit 1.
%e On move 2, travel 1 unit right, reaching the middle digit 3.
%e On move 3, travel 3 units right (wrapping around), reaching the most significant 1 digit again.
%e On move 4, travel 1 unit right, reaching the second digit 1 (again).
%e On move 5, travel 1 unit right, reaching the middle digit 3 (again).
%e Thus, a(11323) = 3.
%o (C++)
%o int a(int n)
%o {
%o int n2 = n;
%o int size = 0; do { n2 /= 10; size++; } while (n2 != 0);
%o int * nums = new int[size];
%o for(int i = size - 1; i >= 0; i--)
%o {
%o nums[i] = n % 10;
%o n /= 10;
%o }
%o int currentIndex = 0;
%o for (int j = 0; j < size; j++)
%o {
%o currentIndex += nums[currentIndex];
%o currentIndex %= size;
%o }
%o int returnVal = nums[currentIndex];
%o delete[] nums;
%o return returnVal;
%o }
%o (Python)
%o def A358647(n):
%o s = list(map(int,str(n)))
%o l, i = len(s), 0
%o for _ in range(l):
%o i = (i+s[i])%l
%o return s[i] # _Chai Wah Wu_, Nov 30 2022
%Y Cf. A357531 (stepping in 1..n).
%K nonn,base,easy
%O 0,3
%A _Moosa Nasir_, Nov 24 2022
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