How old was Allen Ginsberg when he wrote Howl?

with a secondhand typewriter,
affection for his friends
of a certain time ilk
came forth at 29 years young.

it captured all the starving,
hysterical, naked, kipling
delicatessen philosophers
that paved the way
for me and my mates.

and here I am at almost 42,
having forgotten a lot of people
who have forgotten me,
a luddite of the lost generation,
the hipsters between Gen X
and the millennials. 

way down in the golden brown
of the green grass
is where the good stuff lasts;
under the bestsellers
are the best artists. 

as I hold up a sign
for the poetry of Kendra Jean
while walking through the Bowery,
hoping to still be scene.