A288349 Partial sums of A059268.

1, 2, 4, 5, 7, 11, 12, 14, 18, 26, 27, 29, 33, 41, 57, 58, 60, 64, 72, 88, 120, 121, 123, 127, 135, 151, 183, 247, 248, 250, 254, 262, 278, 310, 374, 502, 503, 505, 509, 517, 533, 565, 629, 757, 1013, 1014, 1016, 1020, 1028, 1044, 1076, 1140, 1268, 1524, 2036

Offset

1,2

Links

Table of n, a(n) for n=1..55.

Formula

a(n) = 2^t + 2^(n-t*(t-1)/2) - t - 2, where t = floor(sqrt(2*n) + 1/2), n>=1.

Example

For n=10, a(10) = 1 + 1 + 2 + 1 + 2 + 4 + 1 + 2 + 4 + 8 = 26.

Mathematica

Accumulate@ Flatten@ Array[2^Range[0, #] &, 10, 0] (* Michael De Vlieger, Jun 11 2017 *)

Prog

(PARI) for(n=1, 100, t=floor(sqrt(2*n)+1/2); print1(2^t+2^(n-t*(t-1)/2)-t-2, ", "));

Crossrefs

Cf. A059268.

Sequence in context: A349729 A027936 A082741 * A099522 A255850 A108464

Adjacent sequences: A288346 A288347 A288348 * A288350 A288351 A288352

Keyword

nonn

Author

Zhining Yang, Jun 08 2017

Status

approved