A257257 Square array A(row,col) = A255127(row,col+1) - A255127(row,col): the first differences of each row of Ludic array.

2, 2, 6, 2, 6, 14, 2, 6, 16, 24, 2, 6, 14, 28, 44, 2, 6, 16, 26, 48, 60, 2, 6, 14, 28, 48, 60, 84, 2, 6, 16, 24, 52, 64, 86, 122, 2, 6, 14, 26, 48, 66, 94, 126, 142, 2, 6, 16, 28, 48, 62, 86, 132, 144, 176, 2, 6, 14, 26, 44, 60, 94, 120, 146, 166, 216, 2, 6, 16, 24, 48, 64, 86, 132, 142, 180, 234, 252

Offset

1,1

Comments

The array A(row,col) is read by downwards antidiagonals as A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), ...

Links

Antti Karttunen, Table of n, a(n) for n = 1..10440; the first 144 antidiagonals of the array

Formula

A(row,col) = A255127(row,col+1) - A255127(row,col).

A(row,col) = 2*A257258(row,col).

Example

The top left corner of the array:
    2,   2,   2,   2,   2,   2,   2,   2,   2,   2,   2,   2,   2,   2,   2
    6,   6,   6,   6,   6,   6,   6,   6,   6,   6,   6,   6,   6,   6,   6
   14,  16,  14,  16,  14,  16,  14,  16,  14,  16,  14,  16,  14,  16,  14
   24,  28,  26,  28,  24,  26,  28,  26,  24,  28,  26,  28,  24,  26,  28
   44,  48,  48,  52,  48,  48,  44,  48,  52,  48,  48,  48,  44,  52,  48
   60,  60,  64,  66,  62,  60,  64,  62,  60,  70,  60,  60,  62,  64,  60
   84,  86,  94,  86,  94,  86,  82,  92,  88,  92,  88,  90,  90,  84,  90
  122, 126, 132, 120, 132, 126, 130, 126, 120, 132, 128, 126, 130, 128, 126
  142, 144, 146, 142, 146, 138, 150, 148, 140, 148, 146, 138, 150, 138, 150
  176, 166, 180, 168, 176, 178, 170, 178, 170, 180, 174, 172, 176, 178, 176
  216, 234, 226, 242, 228, 226, 240, 218, 234, 246, 220, 230, 234, 226, 234
  252, 270, 254, 274, 258, 254, 258, 276, 262, 266, 258, 256, 264, 276, 264
  274, 284, 268, 284, 304, 270, 282, 278, 294, 282, 282, 276, 282, 288, 292
  308, 316, 314, 316, 320, 316, 312, 308, 324, 336, 316, 302, 316, 314, 322
  360, 360, 354, 368, 360, 372, 370, 368, 352, 360, 380, 354, 370, 380, 352
  412, 434, 424, 420, 426, 440, 426, 420, 432, 424, 422, 444, 424, 422, 430
  ...

Prog

(Scheme)
(define (A257257 n) (A257257bi (A002260 n) (A004736 n)))
(define (A257257bi row col) (- (A255127bi row (+ 1 col)) (A255127bi row col))) ;; Code for A255127bi given in A255127.

Crossrefs

Column 1: A256482.

Cf. A255127.

Cf. A257258 (same array but with terms divided by 2).

Cf. also arrays A257251 and A257255.

Sequence in context: A255049 A187564 A138061 * A257251 A068555 A167556

Adjacent sequences: A257254 A257255 A257256 * A257258 A257259 A257260

Keyword

nonn,tabl

Author

Antti Karttunen, Apr 19 2015

Status

approved