A364289 Numbers k such that A243071(k) >= k.

3, 5, 6, 7, 10, 11, 12, 13, 14, 17, 19, 20, 21, 22, 23, 24, 26, 28, 29, 31, 33, 34, 37, 38, 39, 40, 41, 42, 43, 44, 46, 47, 48, 51, 52, 53, 55, 56, 57, 58, 59, 61, 62, 65, 66, 67, 68, 69, 71, 73, 74, 76, 78, 79, 80, 82, 83, 84, 85, 86, 87, 88, 89, 91, 92, 93, 94, 95, 96, 97, 99, 101, 102, 103, 104, 106, 107, 109

Offset

1,1

Comments

If k is present, then 2*k is also present, and vice versa.

Links

Table of n, a(n) for n=1..78.

Prog

(PARI)
A064989(n) = { my(f=factor(n>>valuation(n, 2))); for(i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f); };
A243071(n) = if(n<=2, n-1, if(!(n%2), 2*A243071(n/2), 1+(2*A243071(A064989(n)))));
isA364289(n) = (A243071(n)>=n);

Crossrefs

Positions of terms <= 0 in A364288.

Cf. A007283 (subsequence), A243071, A364290 (complement).

Cf. also A364287.

Sequence in context: A154663 A028983 A232682 * A352826 A335657 A038550

Adjacent sequences: A364286 A364287 A364288 * A364290 A364291 A364292

Keyword

nonn

Author

Antti Karttunen, Jul 25 2023

Status

approved