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A255423
The least number k > A255334(n) for which A000203(k) = A000203(A255334(n)) and A007947(k) = A007947(A255334(n)), where A000203 gives the sum of divisors, and A007947 gives the squarefree kernel of n.
6
2058, 10290, 22638, 26754, 34986, 39102, 47334, 51450, 59682, 52728, 63798, 76146, 84378, 88494, 96726, 109074, 113190, 121422, 125538, 133770, 137886, 146118, 150234, 162582, 170814, 174930, 183162, 195510, 199626, 207858, 211974, 220206, 224322, 232554, 236670, 249018, 257250, 261366, 269598, 281946, 286062, 294294
OFFSET
1,1
LINKS
FORMULA
a(n) = A255424(n) * A255426(n).
PROG
(PARI)
A007947(n) = factorback(factorint(n)[, 1]);
nextone(n) = { if(!n, return(0)); my(r=A007947(n), s=sigma(n), k=n+r); while(k<s, if((sigma(k) == s)&&(A007947(k) == r), return(k), k = k+r)); return(0); };
i=0; for(n=1, 2^25, k = nextone(n); if(k, i++; write("b255423.txt", i, " ", k))); \\ Andrew Lelechenko, May 09 2014
CROSSREFS
Cf. also A255335 (same sequence sorted into ascending order), A255424 (squarefree kernel of a(n)), A255426 (same terms with but with their squarefree kernel divided out of them).
Sequence in context: A252112 A045055 A255335 * A202418 A069427 A357918
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 06 2015
STATUS
approved