A277810 Square array A(r,c) = A019565(A277820(r,c)), read by descending antidiagonals as A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), etc.

2, 6, 3, 10, 15, 30, 210, 21, 14, 5, 22, 1155, 462, 35, 70, 858, 39, 910, 55, 330, 105, 1870, 3315, 72930, 5005, 2002, 33, 42, 9699690, 5187, 2926, 85, 714, 2145, 770, 7, 46, 111546435, 238602, 11305, 248710, 3927, 390, 77, 154, 4002, 87, 93763670, 21505, 152490, 440895, 3094, 91, 546, 231, 7130, 13485, 620310, 1078282205, 2306486, 9867, 114114, 17017, 170170, 1365, 2310

Offset: 1

Author

Antti Karttunen, Nov 01 2016

Keywords

• nonn
• tabl

Comments

Permutation of squarefree numbers (A005117) after their initial term 1.

Examples

			The top left corner of the array:
    2,    6,     10,   210,      22,    858,      1870,    9699690
    3,   15,     21,  1155,      39,   3315,      5187,  111546435
   30,   14,    462,   910,   72930,   2926,    238602,   93763670
    5,   35,     55,  5005,      85,  11305,     21505, 1078282205
   70,  330,   2002,   714,  248710, 152490,   2306486,   60138078
  105,   33,   2145,  3927,  440895,   9867,   1870935,  691587897
   42,  770,    390,  3094,  114114, 520030,    162690,  581334754
    7,   77,     91, 17017,     133,  33649,     50141, 6685349671
  154,  546, 170170,   570,    6118, 254562, 357505330,   51269790
  231, 1365,   7293,  3135, 1312311, 983535,  11599797,  589602585
		

Links

• Antti Karttunen, Table of n, a(n) for n = 1..1540; the first 55 antidiagonals of the array

Crossrefs

Transpose: A277809.

The topmost row: A123098, the leftmost column: A277811.

Cf. A005117, A019565, A277820.

Programs

Scheme

(define (A277810 n) (A277810bi (A002260 n) (A004736 n)))
(define (A277810bi row col) (A019565 (A277820bi row col)))

Formula

A(r,c) = A019565(A277820(r,c)).