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A371307
The smallest nonpalindromic number in base n that shares the same prime divisors as its digit reversal in base n.
1
135, 32, 8, 8, 245, 12, 16, 16, 1089, 15, 72, 24, 468, 28, 32, 32, 108, 24, 48, 40, 98, 44, 144, 39, 1800, 52, 392, 35, 27869, 60, 64, 64, 45, 68, 216, 72, 162, 76, 400, 48, 75809, 48, 968, 88, 4590, 92, 288, 60, 238, 100, 1352, 104, 242, 63, 120, 112, 143370, 72, 1800, 120, 640, 124, 105
OFFSET
2,1
COMMENTS
The largest value in the first 500 terms is a(478) = 109443357.
LINKS
EXAMPLE
a(2) = 135 as 135 = 3^3 * 5 = 10000111_2 whose digit reversal is 11100001_2 = 225 = 3^2 * 5^2, both of which have 3 and 5 as prime divisors.
a(10) = 1089 as 1089 = 3^2 * 11^2 whose digit reversal is 9801 = 3^4 * 11^2, both of which have 3 and 11 as prime divisors. See also A110819.
a(14) = 468 as 468 = 2^2 * 3^2 * 13 = 256_14 whose digit reversal is 652_14 = 1248 = 2^5 * 3 * 13, both of which have 2, 3, and 13 as prime divisors.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Scott R. Shannon, May 03 2024
STATUS
approved