This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A052022 Smallest number m larger than prime(n) such that prime(n) = sum of digits of m and prime(n) = largest prime factor of m (or 0 if no such number exists). 7
 12, 50, 70, 308, 364, 476, 1729, 4784, 9947, 8959, 38998, 588965, 179998, 1879859, 5988788, 38778989, 79693999, 287978998, 1489989599, 4595969989, 6888999949, 45999897788, 197999598599, 3999966997975, 6849998899886, 7885998969988, 35889999789995, 39969896999968 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS Does there exist a solution for every prime p? LINKS EXAMPLE p=43 -> a(14)=179998 -> 1+7+9+9+9+8 = 43 and 179998 = 2*7*13*23*43. p=47 -> a(15)=1879859 -> 1+8+7+9+8+5+9 = 47 and 1879859 = 23*37*47*47. MAPLE A052022(n) = {   local( p, m );   p=prime(n) ;   for(k=2, 1000000000,     m=k*p;     if( A007953(m) == p && A006530(m) == p,         return(m) ;     )   ) ; } # R. J. Mathar, Mar 02 2012 MATHEMATICA snm[n_]:=Module[{k=2, p=Prime[n], m}, m=k p; While[Total[ IntegerDigits[ m]]!=p||FactorInteger[m][[-1, 1]]!=p, k++; m=k p]; m]; Array[snm, 18, 2] (* Harvey P. Dale, Feb 28 2012 *) CROSSREFS Cf. A052018, A052019, A052020, A052021, A007953, A005349, A028834. Sequence in context: A041274 A029586 A081292 * A110907 A009937 A009932 Adjacent sequences:  A052019 A052020 A052021 * A052023 A052024 A052025 KEYWORD nonn,base,nice AUTHOR Patrick De Geest, Nov 15 1999 EXTENSIONS a(20)-a(29) from Donovan Johnson, May 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 6 04:14 EST 2019. Contains 329784 sequences. (Running on oeis4.)