A069885 Duplicate of A069748.
1, 2, 7, 11, 101, 111, 1001, 10001, 10101, 11011, 100001, 101101, 110011, 1000001
Offset: 1
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A069748(10)=10101 is the eighth number of A069748 having only digits 0 and 1. The binary number 10101 equals 21 in decimal. Thus a(8)=21.
For[i = 1, i < 1000000, i++, tmp = IntegerDigits[i^3, 11]; If[tmp == Reverse[tmp], Print[i]];]; (* Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 13 2006 *)
isok(k) = my(d=digits(k^3, 11)); Vecrev(d) == d; \\ Michel Marcus, Aug 02 2022
from itertools import count, islice from sympy.ntheory import is_palindromic as ispal def agen(start=0): yield from (k for k in count(start) if ispal(k**3, 11)) print(list(islice(agen(), 17))) # Michael S. Branicky, Aug 02 2022
a(3) = 11 because 11^3 = 1331 is a palindrome.
Do[ p = Prime[n]; f = p^3; If[ f == FromDigits[ Reverse[ IntegerDigits[ f ] ] ], Print[ {n, p, f} ]], {n, 1, 200000} ]
from sympy import nextprime def ispal(n): s = str(n); return s == s[::-1] p = 2 while True: if ispal(p**3): print(p) p = nextprime(p) # Michael S. Branicky, Feb 07 2021
a(3) = 1331 because 11^3 = 1331 is a palindrome and 11 is a prime.
Do[ p = Prime[n]; f = p^3; If[ f == FromDigits[ Reverse[ IntegerDigits[ f ] ] ], Print[ {n, p, f} ]], {n, 1, 200000} ]
Select[Prime[Range[200]]^3,PalindromeQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jan 26 2021 *)
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