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A317538
Indices m for which A317413(m) = 1.
3
1, 4, 6, 9, 12, 16, 19, 21, 24, 28, 30, 33, 37, 40, 43, 45, 48, 52, 54, 57, 60, 64, 67, 69, 73, 76, 78, 81, 85, 88, 91, 93, 96, 100, 102, 105, 108, 112, 115, 117, 120, 124, 126, 129, 133, 136, 139, 141, 145, 148, 150, 153, 156, 160, 163, 165, 169, 172, 174, 177, 181, 184, 187, 189, 192, 196, 198, 201, 204
OFFSET
1,2
FORMULA
a(n) = 3*(n-1) + 1 - A073089(n).
PROG
(Python)
n, f, i, p, q, base = 1, 1, 0, 0, 1, 2
while i < 10000000:
i, p, q = i+1, p*base, q*base
if i == f:
p, n = p+1, n+1
f = f*n
n, a, j = 0, 0, 0
while p%q > 0:
a, f, p, q = a+1, p//q, q, p%q
if f == 1:
n = n+1
print(n, a-1)
CROSSREFS
Sequence in context: A144922 A298864 A310667 * A310668 A185595 A310669
KEYWORD
nonn
AUTHOR
A.H.M. Smeets, Jul 30 2018
STATUS
approved