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 A062100 Triangular numbers with every digit a triangular number. 1
 0, 1, 3, 6, 10, 36, 66, 136, 300, 630, 666, 3003, 3160, 10011, 13366, 16110, 60031, 66066, 106030, 163306, 303031, 333336, 336610, 600060, 630003, 1010331, 1030330, 1063611, 1313010, 3306306, 3316600, 6601161, 10006101, 11066160, 13336030, 16310616, 30330366 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Harry J. Smith, Table of n, a(n) for n = 1..200 EXAMPLE a(6) = 36 is a triangular number, 3 and 6 are also triangular numbers. MATHEMATICA Select[FromDigits/@Tuples[{0, 1, 3, 6}, 8], IntegerQ[(Sqrt[8#+1]-1)/2]&] (* Harvey P. Dale, Nov 05 2011 *) PROG (PARI) TD(x)= { return(x==0 || x==1 || x==3 || x==6) } { n=t=0; for (m=0, 10^9, t+=m; x=t; td=1; while (x>9, d=x-10*(x\10); if (!TD(d), td=0; break); x\=10); if (td && TD(x), write("b062100.txt", n++, " ", t); if (n==200, break)) ) } \\ Harry J. Smith, Aug 01 2009 CROSSREFS Cf. A000217. Sequence in context: A151376 A066245 A068821 * A262242 A339783 A317361 Adjacent sequences:  A062097 A062098 A062099 * A062101 A062102 A062103 KEYWORD nonn,base,easy AUTHOR Amarnath Murthy, Jun 16 2001 EXTENSIONS Corrected and extended by Larry Reeves (larryr(AT)acm.org), Jun 22 2001 Offset corrected by Harry J. Smith, Aug 01 2009 More terms from Harvey P. Dale, Nov 05 2011 STATUS approved

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Last modified August 3 14:40 EDT 2021. Contains 346438 sequences. (Running on oeis4.)