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A263172 Nonpalindromic positive integers whose digits can be rearranged to form a palindrome, after evaluation. 1
10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 112, 113, 114, 115, 116, 117, 118, 119, 122, 133, 144, 155, 166, 177, 188, 199, 200, 211, 220, 221, 223, 224, 225, 226, 227, 228, 229, 233, 244, 255, 266, 277, 288, 299, 300, 311, 322, 330 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Called Dennis numbers as a tribute to user Dennis for winning the robbers' part of The Programming Language Quiz of the Programming Puzzles & Code Golf Stack Exchange website.

Number of d-digit terms for d in [1..8]: [0, 9, 162, 846, 10044, 55548, 608472, 3911256]. - Jon E. Schoenfield, Oct 11 2015

LINKS

Jon E. Schoenfield, Table of n, a(n) for n = 1..10000

Programming Puzzles & Code Golf Stack Exchange, Generate Dennis Numbers, Sep 11 2015.

EXAMPLE

10 is in the sequence since rearranging the 1 and 0 gives the digit string "01", which evaluates to 1, which is a palindrome.

16612 is in the sequence since its digits can be rearranged (as 16261 or 61216) to form a palindrome.

212 is not in the sequence since it is already palindromic.

Since all one-digit numbers are already palindromic, they are not in the sequence.

MATHEMATICA

palQ[n_] := Block[{d = IntegerDigits@ n}, d == Reverse@ d]; Select[Range@ 330, And[! palQ@ #, AnyTrue[FromDigits /@ Permutations@ IntegerDigits@ #, palQ]] &] (* Michael De Vlieger, Nov 03 2015, Version 10 *)

PROG

(Rust) fn d(mut i:u64)->(u64, i32){for n in 1..{let mut o=0; if n.to_string()==n.to_string().chars().rev().collect::<String>(){continue}let mut s=n.to_string().into_bytes(); for a in 0..s.len(){for b in a+1..s.len(){s.swap(a, b); {let t=s.iter().skip_while(|&x|*x==48).collect::<Vec<&u8>>(); if t.iter().cloned().rev().collect::<Vec<&u8>>()==t{o+=1}}s.swap(a, b); }}if o>0{i-=1; if i<1{return(n, o)}}}(0, 0)} //Program written by Programming Puzzles & Code Golf Stack Exchange user "Doorknob" on September 12, 2015

CROSSREFS

Cf. A002113.

Sequence in context: A096092 A109597 A194233 * A008592 A158814 A118959

Adjacent sequences:  A263169 A263170 A263171 * A263173 A263174 A263175

KEYWORD

nonn,base

AUTHOR

Matthew McCaskill, Oct 11 2015

STATUS

approved

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Last modified October 15 05:43 EDT 2019. Contains 328026 sequences. (Running on oeis4.)