A168573 - OEIS

%I #12 Dec 15 2017 17:37:08

%S 15,34,44,106,115,134,142,155,213,214,314,321,334,404,453,515,713,

%T 1006,1046,1114,1115,1142,1214,1234,1263,1402,1403,1555,1703,1849,

%U 2021,2031,2103,2123,2234,2306,2342,2434,2761,3046,3062,3106,3134,3142,3153,3214

%N Numbers requiring exactly one step to reach 14 using map n -> sum of largest digit of all divisors of n (A168239).

%D J. Earls, "Black Hole 14," Mathematical Bliss, Pleroma Publications, 2009, pages 18-22. ASIN: B002ACVZ6O

%H Charles R Greathouse IV, <a href="/A168573/b168573.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[15,2200],Total[Max[IntegerDigits[#]]&/@Divisors[#]]==14&] (* _Harvey P. Dale_, May 22 2012 *)

%o (PARI) is(n)=sumdiv(n, d, vecmax(eval(Vec(Str(d)))))==14&&n>14 \\ _Charles R Greathouse IV_, May 22 2012

%K base,nonn

%O 1,1

%A _Jason Earls_, Nov 30 2009