A227508 - OEIS

A227508

Numbers n such that n! is divisible by R(n), the digit reversal of n.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 18, 19, 20, 21, 22, 23, 24, 25, 27, 29, 30, 31, 32, 33, 36, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Numbers n for which A004086(n) divides A000142(n).

LINKS

Table of n, a(n) for n=1..67.

EXAMPLE

12 is a member since R(12)=21 divides 12! while 13 is not a member as 31 does not divide 13!.

MAPLE

read("transforms"):

isA227508 := proc(n)

if modp(n!, digrev(n)) = 0 then

true;

else

false ;

end if;

end proc:

A227508 := proc(n)

if n = 1 then

else

for a from procname(n-1)+1 do

if isA227508(a) then

return a;

end if;

end do:

end if;

end proc: # R. J. Mathar, Jul 20 2013

MATHEMATICA

Select[Range[79], Divisible[#!, FromDigits[Reverse[IntegerDigits[#]]]] &]

CROSSREFS

Cf. A000142, A004086.

Sequence in context: A193457 A161950 A111470 * A246200 A262356 A277861

Adjacent sequences: A227505 A227506 A227507 * A227509 A227510 A227511

KEYWORD

nonn,base

AUTHOR

Jayanta Basu, Jul 14 2013

STATUS

approved