[R] jump in sequence

[Adrian DUSA]

Dear list,

This should be a simple one, I just cannot see it.
I need to generate a sequence of the form:
4  5  6 13 14 15 22 23 24

That is: starting with 4, make a 3 numbers sequence, jump 6, then another 3
and so on.
I can create a whole vector with:
myvec <- rep(rep(c(F, T, F), rep(3, 3)), 3)

Then see which are TRUE:
which(myvec)
[1]  4  5  6 13 14 15 22 23 24


I'd like to avoid creating the whole vector if possible; for very large ones
it can be time consuming. There should be a way to only create the proper
indexes...

Thanks for any hint,
Adrian

-- 
Adrian Dusa
Romanian Social Data Archive
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Romania
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