_C_r_e_a_t_e _A _V_e_c_t_o_r _o_f _S_e_q_u_e_n_c_e_s
	
	     sequence(nvec)
	
	_A_r_g_u_m_e_n_t_s:
	
	        nvec : an integer vector each element of which
	               specifies the upper bound of a sequence.
	
	_D_e_s_c_r_i_p_t_i_o_n:
	
	     For each element of nvec the sequence seq(nvec[i]) is
	     created. These are appended and the result returned.
	
	_S_e_e _A_l_s_o:
	
	     gl, seq, rep.
	
	_E_x_a_m_p_l_e_s:
	
	     # return the concatenated sequences 1:3 and 1:2.
	     > sequence(c(3,2))
	     [1] 1 2 3 1 2