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 A049502 Major index of n, 2nd definition. 10
 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 2, 2, 0, 1, 0, 0, 0, 1, 2, 2, 3, 4, 3, 3, 0, 1, 2, 2, 0, 1, 0, 0, 0, 1, 2, 2, 3, 4, 3, 3, 4, 5, 6, 6, 4, 5, 4, 4, 0, 1, 2, 2, 3, 4, 3, 3, 0, 1, 2, 2, 0, 1, 0, 0, 0, 1, 2, 2, 3, 4, 3, 3, 4, 5, 6, 6, 4, 5, 4, 4, 5, 6, 7, 7, 8, 9, 8, 8, 5, 6, 7, 7, 5, 6, 5, 5, 0, 1, 2, 2, 3, 4, 3, 3, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,11 COMMENTS a(A023758(n)) = 0; a(A101082(n)) > 0. - Reinhard Zumkeller, Jun 17 2015 REFERENCES D. M. Bressoud, Proofs and Confirmations, Camb. Univ. Press, 1999; cf. p. 89. LINKS Lars Blomberg, Table of n, a(n) for n = 0..10000 FORMULA Write n in binary; add positions where there are 1's followed by 0's, counting from right. EXAMPLE 83 = 1010011 has 1's followed by 0's in positions 2 and 5 (reading from the right), so a(83)=7. MAPLE A049502 := proc(n)     local a, ndgs, p ;     a := 0 ;     ndgs := convert(n, base, 2) ;     for p from 1 to nops(ndgs)-1 do         if op(p, ndgs)- op(p+1, ndgs) = 1 then             a := a+p ;         end if;     end do:     a ; end proc: # R. J. Mathar, Oct 17 2012 MATHEMATICA Table[Total[Flatten[Position[Partition[Reverse[IntegerDigits[n, 2]], 2, 1], _?(#=={1, 0}&)]]], {n, 0, 110}] (* Harvey P. Dale, Oct 05 2013 *) PROG (Haskell) a049502 = f 0 1 where    f m i x = if x <= 4                 then m else f (if mod x 4 == 1                                   then m + i else m) (i + 1) \$ div x 2 -- Reinhard Zumkeller, Jun 17 2015 (Python) def m(n):     x=bin(int(n))[2:][::-1]     s=0     for i in range(1, len(x)):         if x[i-1]=="1" and x[i]=="0":             s+=i     return s for i in range(0, 10001):     print str(i)+" "+str(m(i)) \\ Indranil Ghosh, Dec 22 2016 CROSSREFS Cf. A049501, A037800. Cf. A023758, A101082. Sequence in context: A004586 A116511 A248211 * A242284 A306595 A292592 Adjacent sequences:  A049499 A049500 A049501 * A049503 A049504 A049505 KEYWORD nonn,base,nice,easy AUTHOR EXTENSIONS More terms from Erich Friedman, Feb 19 2000 STATUS approved

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Last modified December 9 19:51 EST 2019. Contains 329879 sequences. (Running on oeis4.)