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

Author

Antti Karttunen, Sep 13 2016

Keywords

• sign
• tabl

Comments

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

Examples

			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
		

Links

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

Crossrefs

Transpose: A276619.

Column 1: A276607.

Cf. A276610, A255127.

Programs

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.

Formula

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