The connection between derivatives of L(s,f) for periodic arithmetical
functions f at s=1 and generalized Stieltjes constants has been noted
earlier. In this paper, we utilize this link to throw light on the arithmetic
nature of L′(1,f) and certain Stieltjes constants. In particular, if p is
an odd prime greater than 7, then we deduce the transcendence of at least
(p−7)/2 of the generalized Stieltjes constants, {γ1(a,p):1≤a<p}, conditional on a conjecture of S. Gun, M. R. Murty and P. Rath.Comment: 11 page