  Aims. The aim of this paper is to characterise the star formation activity in
the poorly studied embedded cluster Serpens/G3-G6, located ~ 45' (3 pc) to the
south of the Serpens Cloud Core, and to determine the luminosity and mass
functions of its population of Young Stellar Objects (YSOs).
  Methods. Multi-wavelength broadband photometry was obtained to sample the
near and mid-IR spectral energy distributions to separate YSOs from field stars
and classify the YSO evolutionary stage. ISOCAM mapping in the two filters LW2
(5-8.5 um) and LW3 (12-18 um) of a 19' x 16' field was combined with JHKs data
from 2MASS, Ks data from Arnica/NOT, and L' data from SIRCA/NOT. Continuum
emission at 1.3 mm (IRAM) and 3.6 cm (VLA) was mapped to study the cloud
structure and the coldest/youngest sources. Deep narrow band imaging at the
2.12 um S(1) line of H2 from NOTCam/NOT was obtained to search for signs of
bipolar outflows.
  Results. We have strong evidence for a stellar population of 31 Class II
sources, 5 flat-spectrum sources, 5 Class I sources, and two Class 0 sources.
Our method does not sample the Class III sources. The cloud is composed of two
main dense clumps aligned along a ridge over ~ 0.5 pc plus a starless core
coinciding with absorption features seen in the ISOCAM maps. We find two
S-shaped bipolar collimated flows embedded in the NE clump, and propose the two
driving sources to be a Class 0 candidate (MMS3) and a double Class I (MMS2).
For the Class II population we find a best age of ~ 2 Myr and compatibility
with recent Initial Mass Functions (IMFs) by comparing the observed Class II
luminosity function (LF), which is complete to 0.08 L_sun, to various model LFs
with different star formation scenarios and input IMFs.
