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A135482 a(n) = (Sum_{i=1..n} 2^prime(i))/4, where prime(i) denotes i-th prime number. 2
0, 1, 3, 11, 43, 555, 2603, 35371, 166443, 2263595, 136481323, 673352235, 35033090603, 584788904491, 2783812160043, 37968184248875, 2289767997934123, 146404956073789995, 722865708377213483, 37616353855796316715, 627912164214501968427, 2989095405649324575275 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..450 (a(0) = 0 added by M. F. Hasler).

FORMULA

a(n) = A076793(n)/4. - M. F. Hasler, Oct 30 2018

MAPLE

A135482:= n-> add(2^ithprime(i)/4, i=1..n): seq(A135482(n), n=0..20); # Wesley Ivan Hurt, Feb 02 2014

MATHEMATICA

Accumulate[Table[Floor[2^i/4], {i, Prime[Range[20]]}]] (* Harvey P. Dale, Dec 05 2013 *)

PROG

(MAGMA) [&+[2^(NthPrime(k)-2): k in [1..n]]: n in [1..25]]; // Bruno Berselli, Sep 24 2015

(PARI) a(n) = sum(k=1, n, 2^prime(k))/4; \\ Michel Marcus, Oct 15 2016

CROSSREFS

Cf. A000040, A000079, A076793, A080355.

Partial sums of A135620.

Sequence in context: A039627 A231497 A051257 * A126614 A000979 A123628

Adjacent sequences:  A135479 A135480 A135481 * A135483 A135484 A135485

KEYWORD

nonn

AUTHOR

Ctibor O. Zizka, Feb 07 2008

EXTENSIONS

More terms from Harvey P. Dale, Dec 05 2013

a(0) = 0 prefixed by M. F. Hasler, Oct 30 2018

STATUS

approved

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Last modified May 28 15:33 EDT 2020. Contains 334684 sequences. (Running on oeis4.)