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A101814
Even Niven (or Harshad) numbers: even numbers that are divisible by the sum of their digits.
2
2, 4, 6, 8, 10, 12, 18, 20, 24, 30, 36, 40, 42, 48, 50, 54, 60, 70, 72, 80, 84, 90, 100, 102, 108, 110, 112, 114, 120, 126, 132, 140, 144, 150, 152, 156, 162, 180, 190, 192, 198, 200, 204, 210, 216, 220, 222, 224, 228, 230, 234, 240, 252, 264, 266, 270, 280, 288
OFFSET
1,1
REFERENCES
David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, p. 171.
LINKS
Richard K. Guy, The Second Strong Law of Small Numbers, Math. Mag, Vol. 63, No. 1 (1990), pp. 3-20.
EXAMPLE
216 is a term of the sequence because it is even and divisible by 9 (= 2+1+6).
MAPLE
s:=proc(n) local N:N:=convert(n, base, 10):sum(N[j], j=1..nops(N)) end:p:=proc(n) if floor(n/s(n))=n/s(n) then n else fi end: seq(p(2*n), n=1..161);
MATHEMATICA
Select[2*Range[200], Divisible[#, Total[IntegerDigits[#]]]&] (* Harvey P. Dale, May 08 2015 *)
PROG
(PARI) isok(n) = !(n%2) && !(n % sumdigits(n)); \\ Michel Marcus, Sep 19 2017
CROSSREFS
Sequence in context: A022483 A100180 A258137 * A034090 A146344 A162763
KEYWORD
nonn,base
AUTHOR
Emeric Deutsch, Dec 16 2004
EXTENSIONS
Edited by Charles R Greathouse IV, Aug 03 2010
STATUS
approved