A027223 a(n) = self-convolution of row n of array T given by A026747.
1, 2, 11, 34, 183, 630, 3384, 12192, 65536, 242232, 1303758, 4900880, 26415708, 100525392, 542639986, 2084879028, 11271483340, 43645729836, 236329734438, 921177944356
Offset: 0