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A328832
Numbers that are sums of distinct primorial numbers, A002110, and do not have a factor of the form p^p.
6
1, 2, 3, 6, 7, 9, 30, 31, 33, 37, 38, 39, 210, 211, 213, 217, 218, 219, 241, 242, 246, 247, 249, 2310, 2311, 2313, 2317, 2318, 2319, 2341, 2342, 2343, 2346, 2347, 2521, 2522, 2523, 2526, 2527, 2529, 2550, 2551, 2553, 2557, 2558, 2559, 30030, 30031, 30033, 30037, 30038, 30039, 30061, 30062, 30063, 30066, 30067, 30069, 30241
OFFSET
1,2
COMMENTS
Numbers n such that A129251(n) = 0 and A328828(n) = 0 (or equally, A328114(n) = 1).
Terms k in A276156 for which A276086(A276085(k)) = k, i.e., those terms of A276156 which are in the range of A276086.
FORMULA
a(n) = A276086(A328833(n)).
PROG
(PARI)
A129251(n) = { my(f = factor(n)); sum(k=1, #f~, (f[k, 2]>=f[k, 1])); };
A328828(n) = { my(i=1, p=2); while(n, if((n%p)>1, return(i)); i++; n = n\p; p = nextprime(1+p)); (0); };
isA328832(n) = ((0==A129251(n)) && (0==A328828(n)));
(PARI)
A276156(n) = { my(p=2, pr=1, s=0); while(n, if(n%2, s += pr); n >>= 1; pr *= p; p = nextprime(1+p)); (s); };
k=0; for(n=1, (2^15)-1, if(!A129251(u=A276156(n)), k++; write("b328832.txt", k, " ", u, " ")));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 30 2019
STATUS
approved