Trying to remember a math term and I could be thinking of something wrong.

Question

When counting by 5’s or 4’s or 3’s as an example, what is the term for the numbers you get by counting that way? 15 is what of 5? Or what is its relationship to 5?

Answer 1

they're arithmetic sequences where d = the common difference

=2 in 2,4,6,...

=3 in 3,6,9,...

=4 in 4,8,12, ...

=5 in 5, 10,15, ...

an= a1+d(n-1) where an= nth term, a1 = 1st term

2 4 6 8 who do we appreciate?

3 6 9 cat of nines tails, whips, a little sadistic but popular on the Mutiny on the Bounty, cats are nice pets, not that bad, even with claws, unless they scratch out your eyes in your sleep. but tabby would never do that. unless you forget to feed her. get one of those new automatic feeders. avoid the claws.

4 8 12 ? what rhymes with twelve? tough one. velvet? close. Melba toast? Melve? Selve, singular of Selves? Selfs?

5 10 15 sweet 16 less 1, forever young until the next term in the sequence. similar to Forever Young, Forever 21, but 20's next so off by 1 again.

or maybe you're looking for geometric sequences

An =A1(r^2-1)/(r-1) with r=2 in the 5,10 almost sequence

15 = 5(2^2-1)/1=15/1=15

but it's really an arithmetic sequence, with d= 5

an = a1 + d(n-1)

a5 = 5 + 5(4) = 25

5, 10, 15, 20, 25 with 25 the 5th term