

A087334


a(1) = 3, then smallest number such that every partial product + 1 is a distinct square.


2



3, 5, 8, 3, 14, 40, 1270, 15874, 251984126, 28673777890680889, 2806729404119595479093401735, 15973219322678152520589944038429546981629762353084607
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


LINKS

Table of n, a(n) for n=1..12.


EXAMPLE

3 + 1 = 4, 3*5 + 1 = 16, 3*5*8 + 1 = 121 etc. are squares.


MATHEMATICA

p = 1; Do[k = 2; While[ !IntegerQ[Sqrt[p*k + 1]], k++ ]; Print[k]; p *= k, {n, 1, 9}] (* Ryan Propper *)


CROSSREFS

Cf. A068559, A087335.
Sequence in context: A019830 A259238 A094355 * A175628 A119360 A021283
Adjacent sequences: A087331 A087332 A087333 * A087335 A087336 A087337


KEYWORD

nonn


AUTHOR

Amarnath Murthy, Sep 06 2003, May 22 2004


EXTENSIONS

Edited by Don Reble, Sep 12 2003
Entry revised by N. J. A. Sloane, Aug 29 2006


STATUS

approved



