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(33s) Ulam Spiral - Gerald H - 08-29-2022 09:36 AM
The Ulam Spiral
https://en.wikipedia.org/wiki/Ulam_spiral
programme returns the indexes of the two difficult neighbouring boxes to the box index provided as integer input.
The programme preserves the stack.
Code:
1. LBL U
2. STO N
3. 4
4. *
5. 2
6. –
7. ENTER
8. SQRT
9. IP
10. STO K
11. CLx
12. 4
13. –
14. SQRT
15. IP
16. K-0.37612771
17. –
18. SGN
19. STO* K
20. CLx
21. N-2*K+3
22. N+ABS(2*K)+5
23. RTN
U: LN = 136 CK = A6C4