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 A173289 Partial sums of A000602. 1
 1, 2, 3, 4, 6, 9, 14, 23, 41, 76, 151, 310, 665, 1467, 3325, 7672, 18031, 42925, 103448, 251732, 618051, 1528777, 3807435, 9539015, 60826848, 60826848, 154666260, 394882063, 1011987677, 2602494798, 6714341561, 17374649352, 45085903121 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Partial sums of number of n-node unrooted quartic trees. Partial sums of number of n-carbon alkanes C(n)H(2n+2) ignoring stereoisomers. The subsequence of primes in this partial sum begins: 2, 3, 23, 41, 151, then no more until a(43) = 1867357583296451. LINKS FORMULA a(n) = SUM[i=0..n] A000602(i). EXAMPLE a(32) = 1 + 1 + 1 + 1 + 2 + 3 + 5 + 9 + 18 + 35 + 75 + 159 + 355 + 802 + 1858 + 4347 + 10359 + 24894 + 60523 + 148284 + 366319 + 910726 + 2278658 + 5731580 + 14490245 + 36797588 + 93839412 + 240215803 + 617105614 + 1590507121 + 4111846763 + 10660307791 + 27711253769. CROSSREFS Cf. A000602, A000598, A000625, A000628, A067608-A067610. Sequence in context: A000381 A001115 A173278 * A096824 A192488 A089797 Adjacent sequences:  A173286 A173287 A173288 * A173290 A173291 A173292 KEYWORD nonn AUTHOR Jonathan Vos Post, Feb 15 2010 STATUS approved

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Last modified December 15 16:41 EST 2018. Contains 318150 sequences. (Running on oeis4.)