A276620 Square array A(row,col) = A276610(row,col+1) - A276610(row,col): the first differences of each row of array A276610, read by descending antidiagonals as A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), ...

4, 4, 8, 4, 10, 10, 4, 8, 12, 20, 4, 10, 12, 20, 16, 4, 8, 12, 22, 12, 24, 4, 10, 10, 24, 16, 26, 38, 4, 8, 10, 24, 14, 30, 40, 20, 4, 10, 14, 22, 14, 20, 38, 18, 34, 4, 8, 10, 16, 12, 32, 34, 14, 22, 40, 4, 10, 10, 22, 20, 26, 38, 22, 34, 68, 36, 4, 8, 12, 28, 14, 18, 40, 14, 26, 46, 36, 22, 4, 10, 12, 20, 8, 30, 48, 12, 30, 74, 28, 14, 34

Offset

1,1

Comments

The first negative term occurs as a(490) = A(25,7) = A276610(25,8) - A276610(25,7) = 248 - 258 = -10.

Links

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

Formula

A(row,col) = A276610(row,col+1) - A276610(row,col).

Example

The top left 18 x 16 corner of the array:
   4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4,  4
   8, 10,  8, 10,  8, 10,  8, 10,  8, 10,  8, 10,  8, 10,  8, 10,  8, 10
  10, 12, 12, 12, 10, 10, 14, 10, 10, 12, 12, 12, 10, 10, 14, 10, 10, 12
  20, 20, 22, 24, 24, 22, 16, 22, 28, 20, 22, 20, 20, 26, 20, 22, 24, 22
  16, 12, 16, 14, 14, 12, 20, 14,  8, 22, 12, 12, 18, 12, 12, 18, 14, 14
  24, 26, 30, 20, 32, 26, 18, 30, 28, 22, 28, 30, 28, 20, 30, 24, 28, 26
  38, 40, 38, 34, 38, 40, 48, 34, 32, 40, 40, 36, 40, 44, 36, 40, 36, 32
  20, 18, 14, 22, 14, 12, 20, 22, 20, 16, 18, 12, 20, 10, 24, 18, 18, 18
  34, 22, 34, 26, 30, 40, 20, 30, 30, 32, 28, 34, 26, 40, 26, 26, 30, 32
  40, 68, 46, 74, 52, 48, 70, 40, 64, 66, 46, 58, 58, 48, 58, 62, 58, 52
  36, 36, 28, 32, 30, 28, 18, 58, 28, 20, 38, 26, 30, 50, 30, 28, 22, 44
  22, 14, 14, 10, 46, 16, 24,  2, 32, 16, 24, 20, 18, 12, 28, 12, 30, 20
  34, 32, 46, 32, 16, 46, 30, 30, 30, 54, 34, 26, 34, 26, 30, 38, 40, 18
  52, 44, 40, 52, 40, 56, 58, 60, 28, 24, 64, 52, 54, 66, 30, 54, 30, 66
  52, 74, 70, 52, 66, 68, 56, 52, 80, 64, 42, 90, 54, 42, 78, 58, 72, 68
  42, 46, 58, 64, 38, 38, 62, 52, 44, 62, 52, 28, 62, 52, 50, 50, 42, 52

Prog

(Scheme)
(define (A276620 n) (A276620bi (A002260 n) (A004736 n)))
(define (A276620bi row col) (- (A276610bi row (+ 1 col)) (A276610bi row col))) ;; Code for A276610bi given in A276610.

Crossrefs

Transpose: A276619.

Column 1: A276607.

Cf. A276610, A255127.

Sequence in context: A273854 A082075 A243641 * A276681 A255485 A322328

Adjacent sequences: A276617 A276618 A276619 * A276621 A276622 A276623

Keyword

sign,tabl

Author

Antti Karttunen, Sep 13 2016

Status

approved