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A185871
(Even,even)-polka dot array in the natural number array A000027, by antidiagonals.
4
5, 12, 14, 23, 25, 27, 38, 40, 42, 44, 57, 59, 61, 63, 65, 80, 82, 84, 86, 88, 90, 107, 109, 111, 113, 115, 117, 119, 138, 140, 142, 144, 146, 148, 150, 152, 173, 175, 177, 179, 181, 183, 185, 187, 189, 212, 214, 216, 218, 220, 222, 224, 226, 228, 230, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 302, 304, 306, 308, 310, 312, 314, 316, 318, 320, 322, 324, 353, 355, 357, 359, 361, 363, 365, 367, 369, 371, 373, 375, 377, 408, 410, 412, 414, 416, 418, 420, 422, 424, 426, 428, 430, 432, 434
OFFSET
1,1
COMMENTS
This is the fourth of four polka dot arrays in the natural number array A000027. See A185868.
row 1: A096376
col 1: A014106
col 2: A071355
diag (5,25,...): A080856
diag (12,40,...): A033586
antidiagonal sums: A048395 (sums of consecutive squares)
FORMULA
T(n,k) = 2*n + (n+k-1)*(2*n+2*k-1), k>=1, n>=1.
EXAMPLE
Northwest corner:
5....12...23...38...57
14...25...40...59...82
27...42...61...84...111
44...63...86...113..144
MATHEMATICA
f[n_, k_]:=2n+(n+k-1)(2n+2k-1);
TableForm[Table[f[n, k], {n, 1, 10}, {k, 1, 15}]]
Table[f[n-k+1, k], {n, 14}, {k, n, 1, -1}]//Flatten
CROSSREFS
Cf. A000027 (as an array), A185868, A185869, A185870.
Sequence in context: A114073 A286242 A360137 * A037007 A357999 A066025
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Feb 05 2011
STATUS
approved