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 A176638 Partial sums of A018190. 0
 1, 2, 5, 12, 34, 115, 446, 1881, 8386, 38472, 179701, 849285, 4047541, 19415118, 93623028, 453486806, 2205081449, 10758731196, 52651373968, 258365785954, 1270930958357, 6265738653554, 30952863554094, 153191072337297 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Partial sums of number of planar simply-connected polyhexes (or benzenoid hydrocarbons) with n hexagons. The only known primes in the partial sum are 2 and 5. LINKS FORMULA a(n) = SUM[i=1..n] A018190(i). EXAMPLE a(6) = 1 + 1 + 3 + 7 + 22 + 81 = 115. CROSSREFS Cf. A000228, A002216, A018190, A038142-A038147. Sequence in context: A032292 A151408 A121956 * A131467 A000103 A101292 Adjacent sequences:  A176635 A176636 A176637 * A176639 A176640 A176641 KEYWORD nonn AUTHOR Jonathan Vos Post, Apr 22 2010 STATUS approved

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Last modified December 3 05:29 EST 2020. Contains 338899 sequences. (Running on oeis4.)