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A254859 Numbers that are both a sum and a product of two or more consecutive primes. 0
15, 30, 77, 143, 210, 221, 323, 1001, 2310, 4199, 5767, 7429, 9797, 10403, 11021, 12317, 20711, 22499, 23707, 25591, 28891, 30030, 33263, 34571, 36863, 38021, 46189, 47053, 75067, 77837, 79523, 82861, 82919, 89951, 95477, 99221, 104927, 111547, 116939, 136891, 141367, 145157, 146969, 154433 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..44.

EXAMPLE

15 is a term because 15 = 3 + 5 + 7 = 3*5.

30 is a term because 30 = 13 + 17 = 2*3*5.

77 is a term because 77 = 2 + 3 + 5 + 7 + 11 + 13 + 17 + 19 = 7*11.

MATHEMATICA

np = NextPrime; pro[n_] := Block[{e, f}, {f, e} = Transpose@ FactorInteger@ n; Length@ f > 1 && Union@ e == {1} && np@ Most@ f == Rest@ f]; seq[lim_] := Union[Reap[Block[{p = 2, q, s}, While[2 p < lim, q = np@p; s = p+q; While[s <= lim, If[pro@s, Sow@s]; q = np@q; s += q]; p = np@p]]][[2, 1]]]; seq[10^5] (* Giovanni Resta, May 05 2016 *)

CROSSREFS

Cf. A050936, A097889.

Sequence in context: A217744 A115811 A110286 * A127526 A249764 A202522

Adjacent sequences:  A254856 A254857 A254858 * A254860 A254861 A254862

KEYWORD

nonn,easy

AUTHOR

Altug Alkan, May 05 2016

STATUS

approved

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Last modified April 19 18:50 EDT 2019. Contains 322290 sequences. (Running on oeis4.)