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A247095 Smallest number m such that A250030(m) = n. 2
8, 7, 6, 5, 13, 30, 29, 157, 317, 626, 3095, 6637, 26833, 145687, 461938, 1068037, 16007153, 54690697 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
A250030(a(n)) = n and A250030(m) != n for m < a(n).
PROG
(Haskell)
import Data.List (elemIndex); import Data.Maybe (fromJust)
a247095 = (+ 5) . fromJust . (`elemIndex` a250030_list)
(PARI) A008474(n)=my(f=factor(n)); sum(i=1, #f~, f[i, 1]+f[i, 2]);
f(n)=my(k); while(n!=5, n=A008474(n); k++); k; \\ A250030
a(n) = my(k=5); while(f(k) != n, k++); k; \\ Michel Marcus, Feb 05 2022
CROSSREFS
Sequence in context: A212410 A328759 A132037 * A124597 A347903 A214023
KEYWORD
nonn,more
AUTHOR
Reinhard Zumkeller, Nov 18 2014
EXTENSIONS
a(17)-a(18) from Michel Marcus, Feb 05 2022
STATUS
approved

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Last modified September 18 07:41 EDT 2024. Contains 375996 sequences. (Running on oeis4.)