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Revision History for A016041

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A016041

Primes that are palindromic in base 2 (but written here in base 10).
(history; published version)

#65 by Michel Marcus at Fri Mar 19 04:10:54 EDT 2021

STATUS

proposed

reviewed

#64 by Amiram Eldar at Fri Mar 19 04:08:29 EDT 2021

STATUS

editing

proposed

#63 by Amiram Eldar at Fri Mar 19 03:55:45 EDT 2021

CROSSREFS

Cf. A095730 (primes whose Zeckendorf- expansion is palindromic), A029971 (primes whose ternary (base-3) expansion is palindromic).

#62 by Amiram Eldar at Fri Mar 19 03:55:32 EDT 2021

CROSSREFS

Intersection of A000040 & and A006995.

#61 by Amiram Eldar at Fri Mar 19 03:54:46 EDT 2021

LINKS

K. Kevin S. Brown, <a href="http://www.mathpages.com/home/kmath359.htm">On General Palindromic Numbers</a>

P. Patrick De Geest, <a href="http://www.worldofnumbers.com/palpri.htm">World!Of Palindromic Primes</a>

CROSSREFS

Intersection of A000040 & A006995.

First row of A095749.

A095741 gives the number of terms in range [2^(2n), 2^(2n+1)].

Intersection of A000040 & A006995. First row of A095749. A095741 gives the number of terms in range [2^(2n), 2^(2n+1)]. Cf. A095730 for (primes whose Zeckendorf-expansion is palindromic and ), A029971 for those (primes whose ternary (base-3) expansion is palindromic).

#60 by Amiram Eldar at Fri Mar 19 03:53:16 EDT 2021

FORMULA

Sum_{n>=1} 1/a(n) = A194097. - Amiram Eldar, Mar 19 2021

CROSSREFS

Cf. A117697 (written in base 2), A002385, A194097, A256081.

STATUS

approved

editing

#59 by Joerg Arndt at Sun Mar 03 01:57:40 EST 2019

STATUS

proposed

approved

#58 by Michel Marcus at Sun Mar 03 01:34:55 EST 2019

STATUS

editing

proposed

#57 by Michel Marcus at Sun Mar 03 01:34:48 EST 2019

MATHEMATICA

lst = {}; Do[ If[ PrimeQ@n, t = IntegerDigits[n, 2]; If[ FromDigits@t == FromDigits@ Reverse@ t, AppendTo[lst, n]]], {n, 3, 50000, 2}]; lst (* syntax corrected by _Robert G. Wilson v_, Aug 10 2009 *)

EXTENSIONS

Syntax of the Mathematica coding corrected by Robert G. Wilson v, Aug 10 2009

STATUS

proposed

editing

#56 by Jon E. Schoenfield at Sat Mar 02 20:38:42 EST 2019

STATUS

editing

proposed