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A052148
Integers k < (reversal of k) such that (reversal of k) + 1 is divisible by k-1.
2
12, 102, 1002, 1079, 10002, 17525, 100002, 1000002, 3124739, 10000002, 100000002, 175247525, 1000000002, 1078012079, 1087921979
OFFSET
1,1
COMMENTS
Numbers 31247524739, 1752475247525, 312475247524739, 1078012078012079, 1078021987912079, 1087912078021979, 1087921987921979, 17524752475247525, and 3124752475247524739 are somewhere in the sequence. - Ed Pegg Jr, Sep 17 2024
EXAMPLE
For k = 12, the reversal of k is 21, 12-1 = 11, 21+1 = 22 and 11 divides 22.
MATHEMATICA
Select[Range[10^7], # < FromDigits[Reverse[IntegerDigits[#]]] && Divisible[FromDigits[Reverse[IntegerDigits[#]]]+1, #-1]&] (* Stefano Spezia, May 29 2024 *)
PROG
(PARI) isok(n) = {d = digits(n); revn = sum(i = 1, #d, d[i]*10^(i - 1)); (revn > n) && (n!=1) && ((revn + 1) % (n - 1) == 0); } \\ Michel Marcus, Aug 22 2013
CROSSREFS
Cf. A004086.
Sequence in context: A356836 A240462 A126533 * A133384 A052067 A307821
KEYWORD
nonn,base,more
AUTHOR
Mary L. Sellers (sellersm(AT)cedarville.edu), Jan 22 2000
EXTENSIONS
a(8)-a(11) from Naohiro Nomoto, Jun 24 2001
a(12)-a(15) from Sean A. Irvine, Oct 26 2021
STATUS
approved