Dear Robert,

Thank you for the detailed explanation.

On the basis of Patisambhidammagga and Dhammapada I think that there
is indeed a kind of jhana based on anicca, dukkha and anatta.

Maybe some exceptional persons with practice of usual jhana in the past,
including past lives, can do without it. For example, the audience of
Aditta-pariyaya sutta.

I will think this over.

Best regards,
Dimitry