How to sum binary binomials in one command?

I'd like to compact the creation of a vector y . It is the rowsum of some binary binomials with a probability each. With rbinom() I tried to define all probabilities at once but I get different results. Here I show the means, but most important to me are the PDFs.

set.seed(8659)
n <- 1e3

a <- rbinom(n, 1, .7)
b <- rbinom(n, 1, .6)
c <- rbinom(n, 1, .05)

df1 <- data.frame(a, b, c, y = a + b + c)
mean(df1$y)
# [1] 1.303

# failed attempt to do this in one command
y <- rbinom(n, 3, c(.7, .6, .05))
mean(y)
# [1] 1.376