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 A190376 a(n) = sum (in ordinary arithmetic) of A067399(k), for k from 2^n to 2^(n+1)-1. 1
 1, 4, 12, 31, 75, 175, 393, 864, 1868, 3978, 8394 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS I was hoping this would turn out to be a known sequence, in which case we would learn something about the average values of A067399. LINKS D. Applegate, M. LeBrun and N. J. A. Sloane, Dismal Arithmetic [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing] MAPLE read("transforms"); numbralADD := proc(a, b) option remember; ORnos(a, b) ; end proc: numbralMUL := proc(a, b) option remember; local p, bshf, s ; p := 0 ; bshf := b ; for s from 0 do if bshf mod 2 <> 0 then p := numbralADD(p, 2^s*a ) ; end if; bshf := floor(bshf/2) ; if bshf = 0 then return p; end if; end do; end proc: isnumbralDiv := proc(n, d) option remember; for e from 0 do if numbralMUL(e, d) = n then return true; elif numbralMUL(e, d) > 2*n then return false; end if; end do: end proc: numbralDivisors := proc(n) option remember; local d, i; d := {} ; for i from 1 to n do if isnumbralDiv(n, i) then d := d union {i} ; end if; end do: d ; end proc: A067399 := proc(n) nops(numbralDivisors(n)) ; end proc: A190376 := proc(n) add(A067399(k), k=2^n..2^(n+1)-1) ; end proc: # R. J. Mathar, May 30 2011 CROSSREFS Cf. A067399, A188548. Sequence in context: A320545 A232580 A133546 * A276785 A171844 A324971 Adjacent sequences:  A190373 A190374 A190375 * A190377 A190378 A190379 KEYWORD nonn,base,more AUTHOR N. J. A. Sloane, May 09 2011 STATUS approved

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Last modified January 25 05:31 EST 2021. Contains 340416 sequences. (Running on oeis4.)