7,26,63,124,X,342

[Sombrero]

X=?

 

[seco services]

215

 

[Sombrero]

lol, i'm good at these things, and got multi choice and still didn't get this one, and chucked my calculator out of the pram.... (

Care to share the obvious with me?

 

[seco services]

one less than the cubes of integers

 

[seco services]

Delete

 

[MisterG]

1 x 7 = 7
2 x (7+6 = 13)
3 x (13+8 = 21)
4 x (21 + 10 = 31)
5 x (31 + 12 = 43)
6 x (43 + 14 = 57)

 

[MisterG]

1 x 7 = 7
2 x (7+6 = 13)
3 x (13+8 = 21)
4 x (21 + 10 = 31)
5 x (31 + 12 = 43)
6 x (43 + 14 = 57)

Lol I over complicated it

 

[Sombrero]

Que?!

 

[EddieM]

no, i don't get it either.

 

[EddieM]

1 x 7 = 7
2 x (7+6 = 13)
3 x (13+8 = 21)
4 x (21 + 10 = 31)

I see no pattern there, no doubt i'm wrong.

 

[chapeau]

It was answered almost immediately

one less than the cubes of integers

7,26,63,124,X,342

(2x2x2)-1 = 7
(3x3x3)-1 = 26
(4x4x4)-1 = 63
(5x5x5)-1 = 124

(6x6x6)-1 = ???

 

[EddieM]

ok I get it :

 

[Sombrero]

one less than the cubes of integers

nice one seco, thanks .