A214548 List of k such that A214686(k) = 1.

2, 3, 5, 7, 9, 11, 17, 25, 33, 35, 37, 39, 43, 45, 51, 57, 61, 63, 65, 69, 71, 73, 77, 79, 85, 91, 97, 103, 105, 109, 115, 121, 123, 127, 129, 137, 141, 153, 167, 171, 177, 179, 183, 185, 193, 199, 211, 213, 221, 225, 229, 235, 241, 245, 249, 255, 259, 261

Offset

1,1

Comments

It seems that a(n) = 1 + floor(sqrt(A214686(a(n)+1)) which complies with an observation of Robert Israel.

Links

Table of n, a(n) for n=1..58.

Robert Israel, A214686

Prog

(Sage)
def A214548_list(n) : # n is a search limit
    a = []; r = 1; f = 1
    for k in (1..n) :
        f = f * k
        if k-1 == gcd(r-1, f) :
            a.append(k); t = 1
        else :
            for t in range(r-1, -1, -1) :
                if gcd(t, f) == 1 : break
        r = (k+1)*(r-t)
    return a
A214548_list(261)

Crossrefs

Sequence in context: A066824 A036963 A120431 * A254440 A284914 A293262

Adjacent sequences: A214545 A214546 A214547 * A214549 A214550 A214551

Keyword

nonn

Author

Peter Luschny, Jul 28 2012

Status

approved