

A098205


A first order iteration: nth term is obtained from (n1)th by adding nth prime and then multiplying by the nth prime; initial value is 0.


1



0, 9, 70, 539, 6050, 78819, 1340212, 25464389, 585681476, 16984763645, 526527673956, 19481523937741, 798742481449062, 34345926702311515, 1614258555008643414, 85555703415458103751, 5047786501512028124790
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OFFSET

1,2


COMMENTS

Difference between sequences generated by this recursion with iv=1[A098206] and iv=0[A098205] provides A070826, i.e. half of nth primorial number. Analogous recursion is A019461.


LINKS

Table of n, a(n) for n=1..17.


FORMULA

a[n]=(a[n1]+p[n])*p[n], a[0]=0.


EXAMPLE

a[4]=(70+p[4])*p[4]=(70+7)*7=490+49=539=


MATHEMATICA

f[x_] :=(f[x1]+Prime[x])*Prime[x]; f[1]=0; Table[f[w], {w, 1, 25}]


CROSSREFS

Cf. A098206, A070826, A019461.
Sequence in context: A110202 A110201 A045739 * A000899 A226013 A156705
Adjacent sequences: A098202 A098203 A098204 * A098206 A098207 A098208


KEYWORD

nonn


AUTHOR

Labos Elemer, Oct 19 2004


STATUS

approved



