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Table of n, a(n) for n=0..31.
L. Euler, De mirabilibus proprietatibus numerorum pentagonalium, par. 29
L. Euler, On the remarkable properties of the pentagonal numbers
G.f.: x*(1+20*x+29*x^2+4*x^3)/(1-x)^5. [Colin Barker, Feb 14 2012]
Equals A000326(n)^2. Cf. A100256.
Sequence in context: A235713 A072471 A017042 * A052501 A193438 A139152
Adjacent sequences: A100252 A100253 A100254 * A100256 A100257 A100258
Ralf Stephan, Nov 13 2004