login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A215408 Smallest number whose home prime (cf. A037274) is the home prime of exactly n natural numbers. 1
2, 6, 4, 42, 10, 118, 250, 140, 4206, 3786, 41933, 1798, 722, 87066, 8691, 5978 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The home primes of the sequence are A118756.
REFERENCES
J. Heleen, Family Numbers: Constructing Primes By Prime Factor Splicing, J. Rec. Math. 28 (1996-97), 116-119.
LINKS
Eric Weisstein's World of Mathematics, Home Prime.
Wikipedia, Home prime
FORMULA
A037274(a(n)) = A118756(n).
EXAMPLE
The home prime of the four numbers 42, 74, 237, and 379 is 379 (for example, 42 = 2*3*7 -> 237 = 3*79 -> 379 which is prime), so a(4) = 42.
CROSSREFS
Cf. A037274, A118756, and their cross-references.
Sequence in context: A322827 A322825 A347555 * A264609 A126262 A330078
KEYWORD
nonn,base
AUTHOR
Jonathan Sondow, Aug 09 2012
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)