help with simple 3d graph

I have a large matrix and want to create a 3d surface of it.
    Suppose the matrix looks something like Matrix K:
    a<-c(1:1200)
    b<-c(rep(1:30,40))
    c<-c(a+b^2)
    K<-data.frame(a,b,c)
    The vector values are not ordered (and repeat themselves as in b).
    Whenever I try commands like "persp" it wants ordered values.
    The only command that approximates what I want is "scatterplot3d"
    (see
    below)
    library(scatterplot3d)
    scatterplot3d(a,b,c)

    Can anybody help me with this. Thanks very much.
    Frank.

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