Answers are grounded in this paper and cite their sources.
A power N=a^k is a semi-selfie number when its digits, in the same order, can be split into groups with plus or minus signs adding up to the base a. This work studies 121 patterns of semi-selfie numbers with first bases from 1 to 2500, and asks which of them still work when the digits of N are read backwards. Of the 121 patterns, 45 are reversible in every line, and 35 of these have a regular reverse pattern. The other 76 are not reversible: 18 reverse only in some lines, 17 fail already in the first line, and 41 end in 0. The work also lists the semi-selfie powers with single-digit bases below 10^11: 94 of the 98 are reversible.
No takes yet. Share an insight, caveat, or question.
Inder Jeet Taneja (2026) studied this question.
Synapse has enriched 8 closely related papers on similar clinical questions. Consider them for comparative context: