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A037050
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Numbers n such that product of n with sum of next n consecutive integers is palindromic.
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1
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OFFSET
| 1,2
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COMMENTS
| 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]
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EXAMPLE
| 187 * (188+189+...+373+374) = 187 * 52547 = palindrome 9826289.
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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
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CROSSREFS
| Cf. A036659, A037051.
Sequence in context: A206288 A037266 A074730 * A036309 A119378 A084998
Adjacent sequences: A037047 A037048 A037049 * A037051 A037052 A037053
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KEYWORD
| nonn,base,hard,more
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AUTHOR
| Patrick De Geest (pdg(AT)worldofnumbers.com), Jan 04 1999.
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