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A224252 Nonpalindromic n such that the factorizations of n and its digital reverse differ only for the exponents order. 2
277816, 618772, 14339143, 34193341, 1125355221, 1225535211, 2613391326, 6231933162, 26157457326, 62375475162, 100504263021, 102407325111, 111523704201, 120362405001, 144326261443, 275603902756, 277816277816, 344162623441, 392739273927, 392875758639 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subset of A110751 and A110819.

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..34 (terms < 2*10^12)

EXAMPLE

277816 and its reverse 618772 are in the sequence since 277816 = 2^3*7*11^2*41 and 618772 = 2^2*7^3*11*41 have the same prime divisors and the same exponents (1,1,2,3).

MATHEMATICA

Do[fn = FactorInteger@n; fr = FactorInteger@ FromDigits@ Reverse@ IntegerDigits@n; If[fn != fr && First /@ fn == First /@ fr && Sort[Last /@ fn] == Sort[Last /@ fr], Print[n]], {n, 15*10^6}]

PROG

(Python)

from sympy import primefactors, factorint

A224252 = [n for n in range(1, 10**6) if n != int(str(n)[::-1]) and primefactors(n) == primefactors(int(str(n)[::-1])) and sorted(factorint(n).values()) == sorted(factorint(int(str(n)[::-1])).values())] # Chai Wah Wu, Aug 21 2014

CROSSREFS

Cf. A110751, A110819, A224253.

Sequence in context: A295472 A162765 A186879 * A236017 A252209 A043601

Adjacent sequences:  A224249 A224250 A224251 * A224253 A224254 A224255

KEYWORD

nonn,base

AUTHOR

Giovanni Resta, Apr 02 2013

STATUS

approved

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Last modified October 17 21:17 EDT 2021. Contains 348065 sequences. (Running on oeis4.)