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A160130
2 x 2 inner (dot) products taken on corresponding digits in Pi and e.
0
13, 11, 12, 18, 82, 74, 50, 58, 34, 44, 60, 121, 81, 36, 51, 19, 13, 49, 52, 48, 36, 12, 44, 53, 33, 68, 59, 9, 41, 53, 48, 30, 4, 36, 104, 100, 35, 52, 94, 51, 26, 87, 63, 81, 108, 45, 81, 108, 54, 9, 45, 85, 54, 14, 81, 123, 66, 105, 105, 52, 58, 48, 32
OFFSET
1,1
COMMENTS
Let pi(n) denote the n-th digit of Pi, and let e(n) denote the n-th digit of e. Define a(n) = pi(n)*e(n) + pi(n+1)*e(n+1).
EXAMPLE
The first two digits of Pi are 3 and 1; the first two digits of e are 2 and 7. Then a(1) = 3*2 + 1*7 = 13.
The second and third digits of Pi are 1 and 4; the corresponding digits in e are 7 and 1; so a(2) = 1*7 + 4*1 = 11.
MATHEMATICA
nn=80; #[[1]]*#[[2]]+#[[3]]*#[[4]]&/@Partition[Riffle[RealDigits[ Pi, 10, nn][[1]], RealDigits[E, 10, nn][[1]]], 4, 2] (* Harvey P. Dale, Jun 13 2011 *)
CROSSREFS
Cf. A000796 (Pi), A001113 (e).
Sequence in context: A152298 A158956 A259663 * A340803 A265770 A359868
KEYWORD
nonn,base,less
AUTHOR
Don Love (moptop35(AT)hotmail.com), May 02 2009
EXTENSIONS
Corrected and extended by Harvey P. Dale, Jun 13 2011
STATUS
approved