We present various identities involving the classical Bernoulli and Euler
polynomials. Among others, we prove that k=0∑[n/4](−1)k(4kn)26kBn−4k(z)=2n+11k=0∑n(−1)k(1+i)k1+ik(kn)Bn−k(2z) and k=1∑n22k−1(2k−12n)B2k−1(z)=k=1∑nk22k(2k2n)E2k−1(z). Applications of our results lead to formulas for Bernoulli and
Euler numbers, like, for instance, nEn−1=k=1∑[n/2]k22k−1(22k−2n)(2k−1n)B2kBn−2k.