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A092612
Product of first n primes that end in 7.
1
7, 119, 4403, 206941, 13865047, 1344909559, 143905322813, 18275975997251, 2503808711623387, 393097967724871759, 65647360610053583753, 12932530040180555999341, 2935684319120986211850407
OFFSET
1,1
LINKS
EXAMPLE
a(1)= 7 = 7
a(2)= 7*17 = 119
a(3)= 7*17*37 = 4403
a(4)= 7*17*37*47 = 206941
MATHEMATICA
Rest[FoldList[Times, 1, Select[Prime[Range[50]], Mod[#, 10]==7&]]] (* Harvey P. Dale, Mar 01 2012 *)
FoldList[Times, Select[Prime[Range[50]], NumberDigit[#, 0]==7&]] (* Requires Mathematica version 12.3 or later *) (* Harvey P. Dale, May 27 2021 *)
CROSSREFS
Sequence in context: A192565 A171209 A296731 * A263943 A302718 A007751
KEYWORD
nonn
AUTHOR
Jorge Coveiro, Apr 11 2004
STATUS
approved