Almost prime
A two-digit number ab is called almost prime if one obtains a two-digit prime number by changing at most one of its digits a and b. (For example, 18 is an almost prime number because 13 is a prime number).
is called almost prime if one obtains a two-digit prime number by changing at most one of its digits and
(For example, 18 is an almost prime number because 13 is a prime number).[1][2][3]
Almost Prime Media
- Almost prime number Cuisenaire rods 6.png
Demonstration, with Cuisenaire rods, of the 2-almost prime nature of the number 6
References
- ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).
- ↑ Rényi, Alfréd A. (1948). "On the representation of an even number as the sum of a single prime and single almost-prime number". Izvestiya Rossiiskoi Akademii Nauk. Seriya Matematicheskaya (in русский). 12 (1): 57–78.
- ↑ Lua error in Module:Citation/CS1/Identifiers at line 630: attempt to index field 'known_free_doi_registrants_t' (a nil value).