|
Search: id:A037050
|
|
|
| A037050 |
|
Numbers n such that product of n with sum of next n consecutive integers is palindromic. |
|
+0
2
|
| |
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
a(5)>1000000, if it exists. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 26 2007
No other terms up to 10^8. - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Sep 10 2007
No additional terms below 10^10 [From Jens Voss (jens(AT)voss-ahrensburg.de), Feb 20 2009]
|
|
EXAMPLE
|
187 * (188+189+...+373+374) = 187 * 52547 = palindrome 9826289.
|
|
MAPLE
|
A036659 := proc(n) n^2*(3*n+1)/2 ; end: isA002113 := proc(n) local b10, i ; b10 := convert(n, base, 10) ; for i from 1 to nops(b10)/2 do if op(i, b10) <> op(-i, b10) then RETURN(false) ; fi ; od ; RETURN(true) ; end: for n from 1 to 1000000 do c := A036659(n) : if isA002113(c) then print(n) ; fi ; od : - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 26 2007
|
|
CROSSREFS
|
Cf. A036659, A037051.
Sequence in context: A062649 A037266 A074730 this_sequence A036309 A119378 A084998
Adjacent sequences: A037047 A037048 A037049 this_sequence A037051 A037052 A037053
|
|
KEYWORD
|
nonn,base,hard,more
|
|
AUTHOR
|
Patrick De Geest (pdg(AT)worldofnumbers.com), Jan 04 1999.
|
|
|
Search completed in 0.002 seconds
|
