login
A112594
Natural function used for generating x^2 and sqrt(x) only using iteration and Q(x) (the characteristic function of sqrt).
0
0, 3, 4, 5, 8, 9, 10, 11, 12, 15, 16, 17, 18, 19, 20, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 80, 81, 82, 83, 84, 85, 86
OFFSET
0,2
COMMENTS
The sequence can be defined as follows: a(0) = 0, a(n+1) = b(a(n)) where b(n) = n + 2*Q(n+4) + 1 (Q is given in A010052)
REFERENCES
R. M. Robinson, Primitive Recursive Functions, Bulletin of the American Mathematical Society, Vol. 53 (1947), pp. 925-942.
FORMULA
a(n) = n + 2*floor(sqrt(n)) = n+2*A000196(n).
CROSSREFS
Cf. A010052.
Sequence in context: A334631 A105020 A286053 * A188003 A120519 A100614
KEYWORD
nonn
AUTHOR
Daniel E. Severin (danielseverin(AT)yahoo.es), Dec 24 2005
STATUS
approved