This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A066528 Non-palindromic triangular numbers whose reverse is a triangular number with the same number of digits. 5
 153, 351, 17578, 87571, 185745, 547581, 1461195, 5911641, 12145056, 12517506, 60571521, 65054121, 304119453, 354911403, 1775275491, 1945725771, 10246462281, 17990863516, 18226464201, 35615002605, 50620051653, 61536809971, 1222080857271, 1664224065406 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Giovanni Resta, Table of n, a(n) for n = 1..64 (terms < 2*10^24) EXAMPLE 153 and 351 are both triangular. MATHEMATICA dtn[L_] := Fold[10#1+#2&, 0, L]; tritest[n_] := Module[{t}, t=Floor[N[Sqrt[2n]]]; 2n==t(t+1)]; A={}; For[i=1, i>0, i++, t=i(i+1)/2; If[tritest[tt=dtn[Reverse[IntegerDigits[t]]]]&&Mod[t, 10]>0&&t=!=tt, AppendTo[A, t]; Print[A]]] CROSSREFS See A069673 for another version. Cf. A066703, A179889. Sequence in context: A253023 A194660 A159294 * A046197 A271730 A056733 Adjacent sequences:  A066525 A066526 A066527 * A066529 A066530 A066531 KEYWORD base,nonn AUTHOR Erich Friedman, Jan 08 2002 EXTENSIONS a(22)-a(24) from Giovanni Resta, Jun 20 2015 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 14 08:54 EDT 2019. Contains 327995 sequences. (Running on oeis4.)