Concatenate Formula every Nth Cells

[pyroto]

I've been at this for hours and wondering if anyone could help.
I am trying to do the following:

Cell H4: =CONCATENATE(C4:C7)
Cell H19 = CONCATENATE(C19:C22)
etc.

So every 15 cells in Column H(starting at H4) shows the concatenate of the the 4 cells every 15 cells in Column C

	Column C	Column D	Column E	Column F	Column G	Column H
1
2
3
4	Bob					BobJerrySusanJordan
5	Jerry
6	Susan
7	Jordan
8	Grace
9	Justin
10	Mathew
11	Lily
12	Carmen
13	Kim
14	Tyson
15	Curtis
16	Peter
17	Jill
18	Karen
19	Kale					KaleHarryJoeBrison
20	Harry
21	Joe
22	Brison

<tbody>
</tbody>

 

[footoo]

=if(mod(row(),15)=4,c4&c5&c6&c7,"")

 

[pyroto]

wow. Seems so simple, but yet more than I knew haha. Thank you thank you!

 

[Peter_SSs]

I would alter it a little so that if rows are added deleted above the data, the formulas don't start giving unexpected results.
In H4, copied down
=IF(MOD(ROWS(H$4:H4),15)=1,C4&C5&C6&C7,"")

 

[pyroto]

Thank you so much!! Works like a charm.

 

[Peter_SSs]

Thank you so much!! Works like a charm.

You're welcome.