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A184392 a(n) = product of palindromic divisors of n. 2
1, 2, 3, 8, 5, 36, 7, 64, 27, 10, 11, 144, 1, 14, 15, 64, 1, 324, 1, 40, 21, 484, 1, 1152, 5, 2, 27, 56, 1, 180, 1, 64, 1089, 2, 35, 1296, 1, 2, 3, 320, 1, 252, 1, 85184, 135, 2, 1, 1152, 7, 10, 3, 8, 1, 324, 3025, 448, 3, 2, 1, 720, 1, 2, 189, 64, 5, 18974736, 1, 8, 3, 70, 1, 10368, 1, 2, 15, 8, 5929, 36, 1, 320, 27, 2, 1, 1008, 5, 2, 3, 59969536, 1, 1620, 7, 8, 3, 2, 5, 1152, 1, 14, 970299, 40 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Indranil Ghosh, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A007955(n) / A179937(n).

EXAMPLE

For n = 20, set of palindromic divisors is {1, 2, 4, 5}; a(12) = 1*2*4*5 = 40.

MATHEMATICA

palQ[n_]:=Module[{idn=IntegerDigits[n]}, idn==Reverse[idn]]; f[n_]:=Times@@Select[Divisors[n], palQ]; Table[f[n], {n, 100}]  (* Harvey P. Dale, Jan 21 2011 *)

PROG

(Python)

def ispal(n):

....if n==int(str(n)[::-1]):return True

....return False

def A184392(n):

....s=1

....for i in range(1, n+1):

........if n%i==0 and ispal(i)==True:

............s*=i

....return s # Indranil Ghosh, Feb 10 2017

CROSSREFS

Cf. A087990, A087991, A088000, A088001, A179937.

Sequence in context: A091136 A140651 A190997 * A007955 A324502 A170826

Adjacent sequences:  A184389 A184390 A184391 * A184393 A184394 A184395

KEYWORD

nonn,base

AUTHOR

Jaroslav Krizek, Jan 12 2011

EXTENSIONS

More terms from Harvey P. Dale, Jan 21 2011

STATUS

approved

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Last modified January 27 17:58 EST 2020. Contains 331296 sequences. (Running on oeis4.)