This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
The top left [0 .. 15] x [0 .. 15] section of the array: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 1, 3, 6, 2, 12, 4, 7, 5, 24, 8, 11, 9, 13, 15, 10, 14 2, 6, 5, 7, 15, 13, 4, 12, 27, 25, 8, 24, 14, 10, 9, 11 3, 2, 7, 6, 13, 12, 5, 4, 25, 24, 9, 8, 15, 14, 11, 10 4, 12, 15, 13, 9, 11, 14, 10, 29, 31, 26, 30, 8, 24, 27, 25 5, 4, 13, 12, 11, 10, 15, 14, 31, 30, 27, 26, 9, 8, 25, 24 6, 7, 4, 5, 14, 15, 12, 13, 26, 27, 24, 25, 10, 11, 8, 9 7, 5, 12, 4, 10, 14, 13, 15, 30, 26, 25, 27, 11, 9, 24, 8 8, 24, 27, 25, 29, 31, 26, 30, 17, 19, 22, 18, 28, 20, 23, 21 9, 8, 25, 24, 31, 30, 27, 26, 19, 18, 23, 22, 29, 28, 21, 20 10, 11, 8, 9, 26, 27, 24, 25, 22, 23, 20, 21, 30, 31, 28, 29 11, 9, 24, 8, 30, 26, 25, 27, 18, 22, 21, 23, 31, 29, 20, 28 12, 13, 14, 15, 8, 9, 10, 11, 28, 29, 30, 31, 24, 25, 26, 27 13, 15, 10, 14, 24, 8, 11, 9, 20, 28, 31, 29, 25, 27, 30, 26 14, 10, 9, 11, 27, 25, 8, 24, 23, 21, 28, 20, 26, 30, 29, 31 15, 14, 11, 10, 25, 24, 9, 8, 21, 20, 29, 28, 27, 26, 31, 30
A003188[n_] := BitXor[n, Floor[n/2]]; A006068[n_] := BitXor @@ Table[Floor[ n/2^m], {m, 0, Log[2, n]}]; A006068[0]=0; A[i_, j_] := A003188[A006068[i] + A006068[j]]; Table[A[i-j, j], {i, 0, 13}, {j, 0, i}] // Flatten (* Jean-François Alcover, Feb 17 2016 *)
def a003188(n): return n^(n>>1)
def a006068(n):
s=1
while True:
ns=n>>s
if ns==0: break
n=n^ns
s<<=1
return n
def T(n, k): return a003188(a006068(n) + a006068(k))
for n in range(21): print([T(n - k, k) for k in range(n + 1)]) # Indranil Ghosh, Jun 07 2017
(define (A268715 n) (A268715bi (A002262 n) (A025581 n))) (define (A268715bi row col) (A003188 (+ (A006068 row) (A006068 col)))) ;; Alternatively, extracting data from array A268820: (define (A268715bi row col) (A268820bi (A006068 row) (+ (A006068 row) col)))
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