square
The 100th pentagonal number is 14950.
There is no equation - the answer is explicit in the name.A pentagonal prism has pentagonal bases. A pentagon has 5 sides. It could not be simpler!
Five.Five.Five.Five.
35.The first few pentagonal numbers are:1-1, five, 12-number, 22-number, 35-number, 51-number, 70-number, 92-number, 117, 145, 176, 210, 247, 287, 330, 376, 425, 477, 532, 590, 651, 715, 782, 852, 925, 1001-numberSource: pentagonal-number
square
The 100th pentagonal number is 14950.
first triple digit pentagonal pyramidal number is 126
There is no equation - the answer is explicit in the name.A pentagonal prism has pentagonal bases. A pentagon has 5 sides. It could not be simpler!
5
square
Five.Five.Five.Five.
A pentagonal pyramid has exactly 6 faces.and a pentagonal prisim has 7
35.The first few pentagonal numbers are:1-1, five, 12-number, 22-number, 35-number, 51-number, 70-number, 92-number, 117, 145, 176, 210, 247, 287, 330, 376, 425, 477, 532, 590, 651, 715, 782, 852, 925, 1001-numberSource: pentagonal-number
126.
pentagonal prism
2:3