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A179937 a(n) = product of non-palindromic divisors of n. 2
1, 1, 1, 1, 1, 1, 1, 1, 1, 10, 1, 12, 13, 14, 15, 16, 17, 18, 19, 200, 21, 1, 23, 288, 25, 338, 27, 392, 29, 4500, 31, 512, 1, 578, 35, 7776, 37, 722, 507, 8000, 41, 12348, 43, 1, 675, 1058, 47, 221184, 49, 12500, 867, 17576, 53, 26244, 1, 21952, 1083, 1682, 59 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,10

LINKS

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

FORMULA

a(n) = A007955(n) / A184392(n).

EXAMPLE

For n = 20, set of non-palindromic divisors is {10, 20}; a(12) = 10*20 = 200.

PROG

(Python)

def ispal(n):

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

....return False

def A179937(n):

....s=1

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

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

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

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

CROSSREFS

Cf. A087990, A087991, A088000, A088001, A184392.

Sequence in context: A063672 A070606 A073731 * A198487 A099613 A209924

Adjacent sequences:  A179934 A179935 A179936 * A179938 A179939 A179940

KEYWORD

nonn,base

AUTHOR

Jaroslav Krizek, Jan 12 2011

EXTENSIONS

More terms from Indranil Ghosh, Feb 10 2017

STATUS

approved

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Last modified May 20 02:50 EDT 2019. Contains 323412 sequences. (Running on oeis4.)