repunit

noun

repunit

noun

Etymology Blend of rep(eated) + unit.

1

A repdigit consisting only of one or more occurrences of the digit 1.

11, 111, and 1,111 are repunits.
The only known prime repunits are R2, R19, R23, and more recently R317 (discovered by Williams in 1978) and R1031 (discovered by Williams & Dubner in 1986). Moreover, Dubner has determined that for every other prime p less than 10000, the repunit Rp is composite.1991, Paulo Ribenboim, The Little Book of Big Primes, page 172:

1 more example

In this study is introduced a novel generalization of repunit and one-zero numbers through the formulation of the generalized One-kZero.2025 November 20, Paula M. M. C. Catarino, Grieg A. Costa, Eudes A. Costa, “On Generalized One-kZero Numbers”, in Axioms, volume 14, number 11, MDPI, →DOI, →ISSN, page 1:

Hypernyms: repdigit

Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.