This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A028337 Palindromes of form n(n+1). 3
 2, 6, 272, 6006, 289982, 2629262, 6039306, 27999972, 28233282, 2704884072, 20278187202, 20591819502, 2592587852952, 2936231326392, 21809166190812, 27237788773272, 229145919541922, 233552101255332, 250087292780052, 2243922442293422, 2570769009670752, 20333113431133302, 27785925652958772 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS P. De Geest, Palindromic pronic numbers of the form n(n+1) Eric Weisstein's World of Mathematics, Palindromic Number. Eric Weisstein's World of Mathematics, Pronic Number. EXAMPLE 272 belongs to the sequence as 272 = 16*17 is a palindrome. MATHEMATICA Select[2*Accumulate[Range[15820000]], IntegerDigits[#] == Reverse[ IntegerDigits[#]]&] (* Harvey P. Dale, Sep 03 2013 *) PROG (Python) A028337_list, n = [], 0 for i in range(2, 10**6, 2): ....n += i ....s = str(n) ....if s == s[::-1]: ........A028337_list.append(n) # Chai Wah Wu, Jan 15 2015 CROSSREFS Cf. A028336. Sequence in context: A232696 A007190 A164829 * A215293 A264410 A135014 Adjacent sequences:  A028334 A028335 A028336 * A028338 A028339 A028340 KEYWORD nonn,base AUTHOR EXTENSIONS a(20)-a(23) from G. C. Greubel, Nov 04 2017 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 22 11:13 EDT 2018. Contains 315270 sequences. (Running on oeis4.)