We show that a combination of the simplest \alpha -attractors and KKLTI models related to Dp-brane inflation covers most of the area in the ( n _ { s } , r ) space favored by Planck 2018 .
For \alpha -attractor models , there are discrete targets 3 \alpha = 1 , 2 , ... , 7 , predicting 7 different values of r = 12 \alpha / N ^ { 2 } in the range 10 ^ { -2 } \gtrsim r \gtrsim 10 ^ { -3 } .
In the small r limit , \alpha -attractors and Dp-brane inflation models describe vertical \beta -stripes in the ( n _ { s } , r ) space , with n _ { s } = 1 - \beta / N , \beta = 2 , { 5 \over 3 } , { 8 \over 5 } , { 3 \over 2 } , { 4 \over 3 } .
A phenomenological description of these models and their generalizations can be achieved in the context of pole inflation .
Most of the 1 \sigma area in the ( n _ { s } , r ) space favored by Planck 2018 can be covered models with \beta = 2 and \beta = 5 / 3 .
Future precision data on n _ { s } may help to discriminate between these models even if the precision of the measurement of r is insufficient for the discovery of gravitational waves produced during inflation .