This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A293601 Limit of rows in rectangular array A292929. 2
 2, -4, 8, -12, 24, -32, 64, -68, 152, -120, 392, -124, 1000, 320, 3056, 2836, 10280, 15112, 38668, 68348, 154152, 297948, 633352, 1269884, 2649892, 5395272, 11157512, 22890976, 47251564, 97224304, 200605456, 413622556, 853809232, 1762332664, 3640315888, 7521114700, 15545862696, 32142131064, 66481012488, 137544496052 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS The g.f. of A292929 is R(x,q) = sqrt( Q(x,q) / Q(x,-q) ), where Q(x,q) = Sum_{n=-oo..+oo} (x - q^n)^n; the g.f. of this sequence equals the limit of the coefficient of x^n in  R(x,q) / q^n  as a power series in q. a(n+1)/a(n) tends to 2.0946... - Vaclav Kotesovec, Oct 23 2017 LINKS Paul D. Hanna, Table of n, a(n) for n = 0..200 FORMULA G.f.: A(q) = 2 - 4*q + 8*q^2 - 12*q^3 + 24*q^4 - 32*q^5 + 64*q^6 - 68*q^7 + 152*q^8 - 120*q^9 + 392*q^10 - 124*q^11 + 1000*q^12 + 320*q^13 + 3056*q^14 + 2836*q^15 + 10280*q^16 + 15112*q^17 + 38668*q^18 +... Let R(x,q) be the g.f. of A292929, then we can illustrate the g.f. of this sequence as follows. The coefficient of x^4 in R(x,q) begins: 2*q^4 - 4*q^5 + 8*q^6 - 12*q^7 + 24*q^8 - 40*q^9 + 38*q^10 +... The coefficient of x^5 in R(x,q) begins: 2*q^5 - 4*q^6 + 8*q^7 - 12*q^8 + 24*q^9 - 32*q^10 + 48*q^11 +... The coefficient of x^6 in R(x,q) begins: 2*q^6 - 4*q^7 + 8*q^8 - 12*q^9 + 24*q^10 - 32*q^11 + 64*q^12 +... The g.f. A(q) equals the limit of the coefficient if x^n in R(x,q)/q^n. CROSSREFS Cf. A292929. Sequence in context: A032473 A084422 A175841 * A171647 A089821 A294067 Adjacent sequences:  A293598 A293599 A293600 * A293602 A293603 A293604 KEYWORD sign AUTHOR Paul D. Hanna, Oct 22 2017 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 December 6 08:53 EST 2019. Contains 329788 sequences. (Running on oeis4.)