The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A251362 Numbers n such that n is the concatenation of distinct prime factors of phi(n), in increasing order. 3
 25, 235741, 23517131 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Next term must be greater than 10^8. Numbers n such that n = A084317(A000010(n)). - Michel Marcus, Dec 06 2014 LINKS EXAMPLE 25 is in the sequence since phi(25)=2^2*5, 235741 is in the sequence since phi(235741)=2^4*3^2*5*7*41, and 23517131 is in the sequence since phi(23517131)=2^7*3*5^2*17*131. MATHEMATICA a251362[n_Integer] := Rest@ Select[Range[n], # == FromDigits[Flatten@IntegerDigits[First@Transpose@FactorInteger[EulerPhi[#]]]] &]; a251362[10^6] (* Michael De Vlieger, Dec 03 2014 *) CROSSREFS Cf. A000010, A000040, A084317, A251363. Sequence in context: A068737 A151649 A122500 * A196520 A228536 A191559 Adjacent sequences:  A251359 A251360 A251361 * A251363 A251364 A251365 KEYWORD nonn,base,more,bref AUTHOR Jahangeer Kholdi, Dec 03 2014 STATUS approved

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

Last modified February 28 23:19 EST 2020. Contains 332353 sequences. (Running on oeis4.)