2, 4, 6, 8, 10 ... "uniquely" are even numbers.

2X 1, 2X2, 2X3, 2X4, 2X5…… ..................... These are all multiples of 2.

2 is the first line, 2X 1.

4 and 6 are the second rows, 2X2 and 2X3.

8, 10 and 12 are the third lines, 2X4, 2X5 and 2X6.

14, 16,18,20 is the fourth line, 2X7, 2x8,2x9,2x10.

See the pattern?

The first line 2= 1X2

At the end of the second line, 6= 2X3.

At the end of the third line, 12= 3X4.

At the end of the fourth line, 20= 4X5.

Think about the square number near 2006, 2025= 45X45.

44X45= 2025-45 = 1980, and at the end of line 44 is 1980.

45X46= 2025+45 =2070, and the end of line 45 is 2070.

Look 1980

If you want to find six digits 123456 and 2468 10, just look at my calculation experience.

500X 500= 25 0000

495 x 495 = 495 "-5 "+5 " =(495-5)(495+5)+5 " = 490 x 500+25 = 245025

496 x 496 = 496 "-4 "+4 " =(496-4)(496+4)+4 " = 492 x 500+ 16 = 2460 16

497 x 497 = 497 "-3 "+3 " =(497-3)(497+3)+3 " = 494 x 500+9 = 247009

According to the box above

496 x497 = 2460 16+496 = 2465 12。 At the end of line 496 is 2465 12.

497X 498= 247009 +497 = 247506, and at the end of line 497 is 247506.

Look at 2465 12

350 x350 = 350 "-50 "+50 " =(350-50)(350+50)+50 " = 300 x400+2500 = 122500

350x351=122500+350 = 122850, and at the end of the 350th line is122850.

35 1 x 352 =122850+351x 2 =122850+702 = 123552, and at the end of the line of 351

Look 122850