OFFSET
1,2
COMMENTS
Also, this is a row of the square array A255741.
Is this sequence related to positive repunits? (see formula section).
LINKS
Felix Fröhlich, Table of n, a(n) for n = 1..10000
Hsien-Kuei Hwang, Svante Janson, and Tsung-Hsi Tsai, Identities and periodic oscillations of divide-and-conquer recurrences splitting at half, arXiv:2210.10968 [cs.DS], 2022, p. 33.
FORMULA
Question: a(2^k) = A002275(k+1), k >= 0. Is this true?
MATHEMATICA
Accumulate@ MapAt[Floor, Array[10*9^(DigitCount[# - 1, 2, 1] - 1) &, 40], 1] (* Michael De Vlieger, Nov 03 2022 *)
PROG
(PARI) lista(nn) = {s = 1; for (n=2, nn, print1(s, ", "); s += 10*9^(hammingweight(n-1)-1); ); } \\ Michel Marcus, Mar 15 2015
(PARI) a(n) = sum(k=1, n, if (k==1, 1, 10*9^(hammingweight(k-1)-1))); \\ Michel Marcus, Mar 15 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, Mar 05 2015
EXTENSIONS
More terms from Michel Marcus, Mar 15 2015
STATUS
approved